The Doctor set the TARDIS destination for home and went to sit beside Rose on the sofa. It had been a very pleasant evening on the Orbital restaurant satellite of Omicron Psi, one of the most famous eating places in the galaxy. Rose had enjoyed herself during the meal and later in the fabulous observation dome where they watched the comet Gallisaa Betan III passing through the Omicron Psi system.

“You never got around to telling me whatever it is you wanted to tell me,” he said as he slid his arm around her shoulders and kissed her lovingly.

“What makes you think I wanted to tell you something?” he asked him.

“I could see it in your eyes all evening,” he answered. “You were itching to tell me something. But you didn’t know how to begin.”

“I didn’t want to spoil the evening,” she told him. “It was really nice. And it does seem ages since we went anywhere, just the two of us. And I really enjoyed it. And I didn’t want it to be spoiled.”

The Doctor caressed his wife’s face gently. She looked fragilely beautiful. She still looked hardly more than a few years older than she did when he first met her. The gauche teenager had blossomed into a sophisticated woman. She wore diamonds now instead of cheap fashion jewellery, and her hair was professionally arranged. But she was still his cockney sparrow. She looked hardly old enough to be the mother of four children. That, of course, was because of the change to her biology that gave her a Gallifreyan lifespan. She would look like she was in her mid-twenties for several centuries, yet. But even he, who arranged for that to happen, was still surprised when he looked at her.

“Rose,” he whispered. “What could you possibly have to tell me that would ruin this evening?”

“I’m pregnant again,” she answered.

“What? No. That’s not possible,” he said. “I’ve been careful. I’m sure…”

She smiled enigmatically and held his hand as it touched her cheek.

“It’s not yours.”

“What?” He drew back from her in astonishment, though his hand remained against hers. His senses reeled. She couldn’t be telling him what he thought he was hearing. It couldn’t be true. She couldn’t have… she never would…

“It’s John Smith’s,” she said after several agonising seconds had gone by.

“Oh.”

She laughed softly.

“You really were worried for a microsecond. I love you. I have never even looked at another man in that way since…. Since Jack kissed me on the Gamestation. Just before he kissed you. You are the only man I have loved, and made love to… except that one time, three months ago, when a Human called John Smith took your place in our bed.”

“When I was… Human… I…”

“Yes.”

“Oh…”

“I’ve been thinking about it ever since I knew. It means that this baby… it won’t be like the others. It will be fully Human, won’t it?”

“Yes. It will. At least I think so. I can’t imagine the engineers who designed the Chameleon Arch ever considered that possibility. I was fully Human. Every trace of my Time Lord DNA was wiped out. Every part of my biology. Oh, but… sweetheart… It’s my fault. I really meant for us to wait. As a Time Lord I could make sure that happened. But as a Human… I needed you so much. I needed the comfort of your love. But I never dreamt that it could…. I am so very sorry.”

“What for? You soppy thing. I’m pleased. I really am. And after all, if you think about it… the twins were so premature. I would still be pregnant now if things had gone the way they should. This baby will be born only a few months after they were due.”

“A Human baby… only nine months gestation. And three months have passed already. It won’t be long at all. Even so… I…”

“If you say you’re sorry one more time, I’ll smack you,” she told him with a glint of the lioness that had first attracted him to her. “Just tell me that you love me, and that you will love this baby as much as you love our other children.”

“Oh, of course, I do,” he told her. “Rose… Yes, I do. Oh, come here…” He hugged her tightly. “Rose, my wife. I am happy. I’m terrified, worried, ashamed. But I am happy, too. And… I wish you had told me in the restaurant. Then we could have celebrated properly.”

“I’d rather do that at home,” Rose answered. “With our children. Oh, Vicki is going to be thrilled. She loves the twins. She’ll be delighted to have another brother or sister.”

“Brenda will go ga-ga. She’s devoted to the twins and Garrick. Davie will never be able to prise her out of the nursery.”

“A Human child… it will have a shorter life than our other children. He… or she… will get old in the usual way, while the others are still young.

“It’ll have a good life, full of love. We’ll all love him, or her.” He smiled warmly as he put his hand over her stomach and felt the life within her. “Do you want to know what it is? It’ll make the personal pronouns much simpler.”

“We knew with all the others. We might as well.”

“It’s a girl,” The Doctor told her. “A healthy Human baby girl.”

“Good. Now we only have one problem.”

“What’s that?”

“Telling my mum.”

“Ah!” The Doctor grimaced. “Mmmm. Are you sure you wouldn’t like to spend a couple of days on the moon of Gallica IV?”

“No. I want to get back to my babies. An evening away from them is long enough.”

“We’ll be home in half an hour,” he promised. “If we’re lucky your mum will be in the City with Christopher and we won’t have to tell her yet.”

“Just long enough for a cuppa,” Rose said.

“I’ll make it,” The Doctor told her. “You stay right there and rest.”

Rose sighed, though not unhappily. Whenever she had broken this sort of news to him The Doctor’s first response was to treat her as if she was fragile and an invalid. He would want to do everything for her, now. Then again, after abandoning her during his brief time as ‘John Smith’, she thought that was only fair. Sometimes she did find herself hankering after the old days when the two of them faced all sorts of dangers together, she fighting alongside him. But she had willingly given up all of that to be the mother of his children. She was more than happy.

When The Doctor returned to the console room, though, she was looking far from happy. She wasn’t sitting down, either. She was at the environmental console frowning over something that had demanded her attention.

“What is it?” he asked, setting the tea tray down before coming to join her.

“A distress signal. The TARDIS has locked onto the source automatically. We’re about to drop out of the vortex.”

The Doctor automatically reached out a hand to hold onto her as it did so with a bump. They both kept their feet and his hands moved across the console as he scanned the ship that had sent the SOS.

“It’s a Chula ship!” he said with an ironic laugh. “Remember, the sort of thing Jack was flying when we met him.”

“His blew up.”

“This one isn’t in any danger of doing that. But there is a fluctuating lifesign aboard. We have to help.”

“I suppose this means we won’t be home in half an hour, after all?” Rose sighed. “No, its ok. I’m just being selfish. I really didn’t want to get stuck into some mystery right now. But of course we have to help. What was it you used to say? Captain of the Carpathia.”

“I’ll try to sort it out as quickly as possible,” The Doctor said. “I want to go home, too.”

He materialised the TARDIS across the bulkhead of the Chula ship. From the outside it would look as if a traditional, space-worthy ship had been welded together with a very unspace-worthy telephone box.

The Doctor opened the TARDIS door and stepped out onto the ship. Rose followed him.

“You should stay in the TARDIS,” he told her.

“The environmental console says it’s safe. There’s no radiation or any known disease aboard. The air is breathable. And there is just one lifesign aboard.”

“Even so…”

“I’m pregnant, not crippled. I can still watch your back. Besides…”

She stopped speaking as the command chair span around to face them. Rose and The Doctor both stared at the figure strapped into position. He was wearing a dark blue all in one uniform with the ensignia of a Chula space captain. They were a humanoid race. This one was about The Doctor’s height, but with no body hair at all and skin that was absolutely coal black. Not the dark brown of Humans usually labelled as ‘black’, but absolutely black. His skin was lined with age, and his hands were gnarled and shrivelled in on themselves, almost crippled with arthritis. His eyes were milky with cataracts.

“The Chuala could do with rethinking their retirement age policy,” Rose commented. “He is alive, isn’t he?”

“Just,” The Doctor answered as he quickly examined the man. He put a hand over his heart. He could feel it racing. He gently soothed and steadied it. The Chuala captain gave a soft sigh as if some of the pain he was suffering had been eased.

“Can you hear me?” The Doctor asked. “I’m The Doctor. I’m going to try to help you. If I can. This is my wife, Rose. Stay with us. What is your name?”

“I’m… I’m sorry,” the Chuala whispered hoarsely. “I’m sorry. It was… my fault. I was afraid…. Afraid to die alone. I hoped somebody would come. But… I’m sorry. You… Now you will… die with me.”

“Doctor!” Rose backed away at those words, but The Doctor told her to come closer.

“Hold his hand. Let him feel some small comfort. He is dying. His body is shutting down rapidly. I can’t do anything to stop it.”

“What’s he dying of?” Rose asked as she gripped the Chuala captain’s hand and felt the slight pressure as he responded to her touch.

“Old age,” The Doctor replied. “Just that. I don’t know why… how somebody so old came to be flying a ship. But…”

The Doctor stopped talking. Again he put his hand over the old man’s heart, steadying it. But he knew it was almost too late. The heart was like a clock winding down. A few more seconds, a few more beats, and then it stopped. The Chuala captain sighed once more. The Doctor reached and closed his eyes and paused a moment in respect to the soul that had flown from the shell of the body.

Rose let go of the hand and stepped back, swallowing hard to suppress the sob that came unbidden.

“We were too late.”

“No, we were in time to comfort him in his last moments,” The Doctor answered. “I don’t think we could have done anything else. Except… I shall have to find out what happened. I’ll download the ship’s log, and bring the body back to the medical room for an autopsy.”

That would take time. It meant they would not be home for several hours. But Rose didn’t object. She understood that he couldn’t just leave the body floating in space. He had to know what had happened.

Because he was the only person who cared enough to find out what happened. Rose watched as he transferred the log to a memory wafer and put it in his pocket. Then he found a piece of tarpaulin used to cover freight and wrapped the body tightly in it, preserving it exactly as it was until he could do that autopsy. He carried it through to the TARDIS.

“Close the door,” he told Rose. “And sit down and drink your tea while it’s still hot. I’ll bring him down to the medical room and be with you in a jiffy.”

The tea was still hot in the teapot. The Chuala captain’s death had been that quick. Rose drank a cup simply out of habit. The Doctor returned presently and went to the console. He slotted in the memory wafer and opened the log.

He was surprised when he saw the face of the Captain reporting on his mission. He looked around thirty or thirty-five years of age. He was a handsome man, a sort of jet black, bald version of Captain Jack, though with less of a devil-may-care attitude. He was solemn as he reported that the ‘payload’ had been delivered. As he continued to speak The Doctor got the distinct impression that he had been charged with delivering some sort of dirty bomb or biological weapon to the homeworld of the enemy. He spoke about the ‘honour’ of being the one to deal such a blow, one that might bring about the final and decisive victory and peace for all freedom-loving people. But the souls of those whose lives would be ended by his action troubled him, all the same.

“There is no glory in such an action,” he said. “I don’t believe it can even be called an act of war. I pray that it does bring peace. That alone would justify such a terrible deed as this.”

An analogy from Earth history occurred to The Doctor. The pilot of the Enola Gay who flew over Japan and dropped the atomic bombs that killed and maimed thousands but brought an end to war for millions. History recorded that he, too, felt the weight of that ‘honour’ upon him.

The Doctor pushed away a memory of when he and his TARDIS had been chosen for that same mission. When he had been sent to destroy the Daleks and bring an end to the Time War. That time the cost had been too great. His own people suffered the same fate as the Daleks. Unlike the Allies of WWII, unlike the Chula in this war, there was no victory. Both sides lost.

The first log entry ended. There was a bleep that indicated the start of another entry. The time stamp showed that it was made about three hours later. The captain looked worried.

“Something is wrong. I am ill. I don’t know what is happening to me, but the nanogenes are not helping. This seems to be something beyond their capability. I am putting the ship in stationary orbit around an uninhabited planetoid while I run a full medical analysis.”

Again there was a bleep. The next entry was twelve hours later than the previous one. The Doctor stared in shock at the man who faced the data recorder now. It was the same man. But his face was different. He looked at least ten years older. And he was scared.

“I am contaminated,” he said. “By the same agent that I delivered to our enemy. I am doomed to die the same death. I cannot return to the Chula homeworld for fear of bringing the infection with me. I will die here, in the ship that brought the same doom to so many. It is… fitting, perhaps. I only wish I could see my family one more time. But I am still so far out of communication range. And even if I were… No, it would hurt them too much. Let them believe I was lost in battle.”

Another bleep. Again there was a time stamp. Another twelve hours had passed. The Doctor guessed that was a standard day in Chula measurement. He was making his daily report, as instructed by his superiors. But a day had wrought huge differences on the face of the man who sat before the recorder. He looked now as if he was in his mid fifties by Earth reckoning. He talked about the changes to his body and the failure to find any way to reverse the damage. He was obviously very scared, but he tried to maintain a professional calm as he completed his report.

The next report, another ten twelve hours later, and he looked like he was in his mid-to late sixties. His face was lined and his voice was dry as he reported that the aging continued at a steady pace and showed no sign of slowing. He added that the average life expectancy for a healthy Chula was about ninety. But he was experiencing pain in his kidneys and wondered if he would actually last another two days.

Twelve years aging every twelve hours. A constant pattern. The Doctor wondered if there was a clue there. Most viruses he had ever heard of had a graduated pattern of symptoms. This was different.

Of course it was, he reflected. It was not a natural illness. It was something created by Chula biologists in a laboratory. It was a manufactured weapon of mass destruction. Why expect it to follow the laws of nature when it was an unnatural thing in itself?

Bleep.

Now the Chula captain had the appearance of a man nearing his eightieth year. He looked as if he was in constant pain. The kidney problem he had complained of was obviously acute now. His hands were stiff and contracted with arthritis and he fumbled at the controls as if he found it hard to see them clearly.

“This is the fate I inflicted on our enemy. Rapid aging. A lifetime lived in a matter of days. Death from the ordinary ills of old age coming to those who were young only a short time ago. It is a terrible, terrible death.”

He confessed then, that he was a military man. He knew little of the science with which his people had developed this weapon. He had not known any details of the deadly payload; he had no idea what he was unleashing on an unsuspecting population. Now he knew. He let out a long, painful sigh and admitted that it made no difference. He would have done his duty, followed the orders of his superior officers even if he had known. Because he was a loyal Chula warrior and he knew that their cause was righteous.

“And yet,” he added. “It is fitting that I should share their torment, that I should die the same way. It was a terrible thing. I only hope that it was enough to end the war. I only hope my own children grow up in peace. Oh, my children. I hope… I hope when they know what I did, that they remember me with pride, not shame.”

He sighed again and reached with shaking hands to stop the recording. There were no more. He must have been too ill by the time the next report was due. The Doctor reckoned it was no more than a day later than the missed report by the time they arrived, just in time to see him die with all the symptoms of a man of a hundred years of age.

He and the Chula Captain had something in common, after all. They both knew the bitterness of a pyrrhic victory.

He looked towards the TARDIS door. They were still connected to the Chula ship. He should find out which planet it was that the payload had been delivered to. If it had been released into the atmosphere then there was probably no hope for the population. It would have been what Earth scientists called a ‘global killer’. But he could at least send out quarantine markers warning against any expedition landing on the planet for however long it would take for the virus to die out. He wondered if there was any point in contacting the Chula government and demanding to know what they thought they were doing with such a weapon, but he knew there would be no point. As well ask President Truman why he thought Hiroshima and Nagasaki were justified.

“Doctor.” Rose’s voice cut into his thoughts. He looked around as she stood up from the sofa. She tried to say something else, but fear constricted her voice. In any case, The Doctor knew from looking at her what the problem was. He was by her side in a few long strides, holding her in his arms.

“We’re contaminated, aren’t we?” she managed to say. “We’re aging like he did. And… and… so is… so is the baby.”

The Doctor touched her stomach. Less than an hour ago there was no obvious outward sign of her pregnancy. Now she looked about five months gone, with her stomach starting to swell beneath her dress.

“The medical room,” he said. She took a step forward, but her legs buckled beneath her. He lifted her in his arms and held her close to him as he turned and ran. Yes, they were both contaminated. He hadn’t even noticed. He had been thinking only of the stricken Chula captain. He hadn’t even considered the possibility of contamination. The environmental console had said it was safe. There had been no biohazard alarm when they stepped back into the TARDIS.

Which, of course, only meant that the Chula biological weapon of mass destruction was so new and innovative that even the TARDIS didn’t recognise the danger.

He should have. He should have considered the possibility. He should have worn a biohazard suit when he went into the Chula ship. He should have sent Rose into an inner room where she would be safe until he had confirmed there was no danger to her and their unborn child.

“It’s my fault,” he thought. He knew that Rose was crying in his arms. He felt like doing the same. But he couldn’t. He had to be strong. She needed him to be strong.

He reached the medical room. He had already brought the wrapped body of the Chula captain and laid him on the main examination table ready to do an autopsy. He brought Rose to the bed in the corner where she could lie comfortably while he examined her and the baby properly.

“I don’t think we’re as badly affected as he was,” The Doctor said. “He aged something like a year for every hour. At my reckoning we’re aging about two months every hour. Our biology is different to his, of course.”

“That’s… only a little bit better,” Rose answered. “That means… we’ll be dead in…”

The maths escaped her. The Doctor had already worked it out. Since they both had a Gallifreyan lifespan of near enough another thousand years, they could last…

Well, long enough for him to work it out, maybe. He had some clues from the Captain’s log reports. A scientific brain like his ought to be able to figure it out in a day or so.

But there was a more immediate problem, and Rose’s expression told him that she had worked it out already.

“Two months every hour,” she said.

“Yes.”

“That means…” She touched her rapidly swelling stomach. She had already unfastened her skirt and slid it off. It was too uncomfortable. “That means the baby… will be due in… in…”

“In about two hours,” The Doctor said. She’s growing rapidly. Lie still. I’m going to give you some shots. Vitamins, iron, calcium, folic acid… and… anything else I can think of by the time I reach the supply cupboard. Just… don’t worry, Rose. I’ll look after you. And our baby. I promise you.”

“I believe you, Doctor,” she answered. She watched him open cupboards and prepare an array of syringes that would pump her body full of everything the growing baby was draining from her. While he injected them into her he gave her a tube of what looked like processed cream cheese and told her to eat it.

“Concentrated cúl nut puree,” he said. “Emergency food rations. Full of protein. There’s another half dozen there. Keep eating them. You and the baby need it. Six months growth in a few hours. It all has to come from somewhere. I’m going to set up a saline drip, too. By the way, would you mind if we called her Sarah Jane? I know we usually spend some time discussing names, but… well… this time…”

“That’s a good name,” Rose answered. “A really good name. But… Oh, Doctor. Should we even think of that? Is she… I mean… It’s not fair. We have time to prepare… but she… she’ll be born… only to die in such a short time. She’s Human… she doesn’t have as much time as we do…”

“Rose,” The Doctor said. “Rose, don’t cry. None of us are going to die here. I promise you. I can’t do anything yet. I have to take care of you and Sarah Jane. But as soon as she’s safely born, I’m going to be on to it. The Chula Captain wasn’t a scientist. He didn’t know how the virus worked. But I am a scientist. And a bloody good one. You know that. I’m going to make this right.”

“I believe you,” she told him. “But, Doctor… if… if you can’t… if it’s beyond even you…”

“I’m The Doctor,” he answered. “I can do anything.”

“Can you…” she gasped. “Oh… I just felt her kick. Doctor… can you… fix the pillows so that my back isn’t killing me. Ohhh… She kicked again. That’s fantastic. But… four months of backache all at once. That’s not fair…”

“You’re doing just fine, sweetheart,” The Doctor assured her. “And so is our little girl. She’s developing perfectly… for just over six months gestation.”

“Doctor… what about… the birth. How are we going to…”

“I’ve been thinking about that, too,” he answered. “It’s going to have to be a very swift caesarean under local anaesthetic. There is no way we can risk a natural birth. We’re not under anything like natural circumstances here. You’re going to have to trust me with all your heart and soul, Rose.”

“I do trust you. That’s a scary kind of prospect. But I do trust you.”

“All right. Then… hang in there for a little while. Count the kicks. I need to get things ready.” He kissed her on the lips and caressed her now very swelled stomach, feeling the movement of his child under his hand and loving that sensation, even in these frightening and uncertain circumstances. Then he made sure she ate another of the cúl nut packets and turned to make the preparations. First, he had to move the corpse of the Chula Captain off the operating table. He would have to wait. He left the body in an alcove behind the computer console and went to sterilise the table and prepare the equipment he would need. He glanced at Rose as she lay on the bed, watching him. She did trust him, implicitly. She must have guessed how dangerous it was. He was going to have to do an operation that usually involved a whole team of nurses, anaesthetists and technicians by himself. Her life and the life of their child were literally in his hands. But she trusted him.

“Who are these Chula anyway?” Rose asked as she watched him work. “And why are they always causing trouble?”

“They’re… believe it or not… actually quite decent people when you get to know them. I really wish they would try to get on with some of the other species in their part of the galaxy. I’m sure they could if they tried. If they stopped building war fleets and used some of their technology for peacetime purposes. The nanogenes for instance. Remember last time. They are a fantastic innovation. With a bit more research and development they could be used to cure just about everything that ails organic beings in the universe, and they’re the only people even looking into that kind of technology at the moment. But they use it for military purposes – for getting their wounded troops repaired and battle ready again, and for…”

He stopped talking. He had thought of something. He glanced towards the place where he had left the corpse of the Chula Captain. Was it really so simple? Was that all there was to it?

He had a theory. But he had no time to test it, yet. Rose was almost ready for him.

“Come on, sweetheart,” he said. “It’s time. Stand up, and walk with me. I’ll help.”

She was close to an eight months gestation now. Not quite full term. But he had to have time to administer the aesthetic and get ready for the first incision. He helped her up onto the table and she lay down quietly, uncomplaining as he injected the local anaesthetic. She didn’t even complain about the fact that it was the tenth syringe he had put into her in the past hour.

He picked up the scalpel and then closed his eyes momentarily. He knew that what he was about to do could go terribly, horribly wrong. But he had to try. There was no other way. There was nobody else who could help.

“I’m ready,” Rose whispered. “Do it, Doctor. Please.”

There’s… there’s a way I can do it,” he said. And he concentrated hard, creating the smallest time fold possible. It covered Rose’s abdomen and his own hands as he made the first incision. For a few minutes, he could hold back the advanced aging, hold back time. Long enough for the baby to be safely born.

Rose watched The Doctor’s face. She couldn’t feel anything. She couldn’t see what he was doing. But she knew from his expression what was happening. Then she saw him lift the baby in his hands. He cleared her mouth and smiled widely as he heard her cry. He cut the umbilical cord and clamped it and gave her into Rose’s hands. The time fold collapsed as he did so and he worked quickly now, removing the placenta, making sure everything was as it should be. And then suturing the incision in her womb and then in her flesh itself. He put a clean gauze over the wound and bandaged it. Then he looked at Rose as she held the child to her breast. She still looked newborn yet. But time was passing for them all. Now there was something else he had to do.

He lifted his wife into his arms again, as she held their baby in hers, and carried her across to the bed once more. He told her to eat some more cúl nut puree. She told him she was sick of the taste of cúl nut puree and she wanted ice cream.

“I’ll get you that when we’re home,” he promised. “Right now…”

He went to the corner where he had put the sad remains of the Chula captain and quickly drew a blood sample from the body. He prepared a slide and studied it carefully. Then he drew some of his own blood and examined it. He went to Rose and drew a little blood from her arm. He looked at their baby. He had been twenty minutes or so at this work. She already looked a month old, with light hair covering her head and deep brown eyes. She had a placid expression on her face. She looked up at The Doctor as he leaned over her.

“She’s beautiful,” he said. “Hold her tight, Rose. Don’t let her go. I’ll be as fast as I can. I promise. I think I know what to do. I just need to be absolutely sure.”

“I know,” she answered him. “But… please don’t be long. You know how much you missed of the twins when you were away. They grew so much in a few weeks. Don’t… don’t miss too much of her…”

“I won’t.” He kissed Rose and the baby and turned to return to his experiment. He worked fast, but he was aware of time passing by faster than it had a right to do. He glanced back at the two of them often and he could see that the baby was continuing to grow. She had reached the development stage of a two month old when he finished examining the blood samples and told Rose he was going to have a look at the Chula ship.

When he returned, she looked like a three month old baby. She had mastered holding onto Rose’s thumb with her hands. She was making happy cooing noises in response to Rose’s voice.

The next stage in her development was the stage he missed with the twins because he was away being John Smith, drifter, avoiding the Followers of The Master. He was going to miss most of it again. But if he got this right, now, at least he wouldn’t miss much more.

“Can you walk?” he asked Rose. He removed the bandages and looked at the scar. It was mended. Three and a half months of aging since the caesarean. Three and a half months of recovering from it. There was that much to be thankful for. Yes, she could walk. He wrapped a blanket around her and the baby and held her as they walked back through the TARDIS corridors to the console room, then through the main door into the Chula ship. He told Rose to sit down on the floor with baby Sarah Jane. She watched as he did something at the life support computer and then knelt in front of her. She was startled to see a sharp scalpel in his hand.

“Remember when we were last inside one of these ships?” he asked. “The rope burns on your hands were mended by the nanogenes in the air.”

“Yes. But… they didn’t save him… the Chula Captain.”

“No, they didn’t. But they can save us. If we show them that they have a job to do.”

Rose gave a soft gasp as she saw him slit his palm with the scalpel. His blood flowed freely for a few seconds before his hand began to glow, surrounded by the microscopic nanogenes that were in the air aboard the Chula ship. He watched them repair the wound, then he reached and took Rose’s hand. He did the same to her.

“The Chula developed a bad nanogene. A deadly one, to use as a weapon against their enemy,” he said. “We know what it does. We’ve seen the results. We’ve experienced them. I’m not sure how the Captain got contaminated by it. He must have had some kind of physical contact with it. Because it seems like that’s how it spreads from an infected body. By physical contact. When the infected body is dead, the nanogenes become inert, incidentally. The Captain’s blood was full of them but they weren’t doing anything else. If we’d arrived a few minutes later, after he was dead, then we would have been ok. But he was still clinging to life. We both touched him. We were infected.”

“Ok…” Rose nodded. She understood that. “But… how does…” She held up her hand as the glow faded.

“The air in this ship is full of ordinary, good nanogenes that mend wounds, cure diseases and so on. But they didn’t know he was ill. He wasn’t wounded. They had no reason to become active. Cutting ourselves… the nanogenes got to work straight away. And of course they would notice that there’s something wrong. They’re working away now inside us, fighting the bad ones. They’ll win, because the bad ones only have one purpose – to kill. Whereas they have millions of functions, all about preserving life and making people better. It will take half an hour or so, I think.”

“What about… What about Sarah Jane?” Rose asked.

“I’m… steeling myself… I have to cut her, too. And that is the last thing I want to do. She is so beautiful. So perfect. And the thought of hurting her…”

“But if you don’t, she’ll die. You have to.”

“Yes,” he said. He held the scalpel in his hand and reached to hold one of her feet. He intended to slice into her heel, the least sensitive place on her body, where it wouldn’t hurt quite so much. His hand shook. He bit his lip and looked at Rose. She reached out and steadied his hand.

“Together,” she said. “We both love her. We’ll both do this for her sake.”

Rose’s hand was over his as he brought the scalpel down on the baby’s foot. They both felt the resistance before it sliced into her flesh. As she cried in pain and shock The Doctor gave an anguished cry and pulled back, throwing the scalpel as far from him as possible. But it had done the job. The nanogenes surrounded her, making her flesh glow. The Doctor reached and hugged his wife and child together as they waited for the work to be done, for them all to be cured.

“It’s done,” he said at last. Another half hour had passed before he was certain. He drew back and looked at the child in Rose’s arms. She looked about five months old.

“About the same as the twins,” Rose pointed out. “They could easily be triplets.”

“Yes,” The Doctor said. “Yes, they can. They can grow up together. We’ll… take her home now. Go and… go and get dressed properly. And find some clothes for her. There are stacks of dresses that Vicki grew out of floating around in the wardrobe.”

“What are you going to do?”

“I’m going to bring the Captain back into his ship and set it on auto pilot to return to the Chula homeworld. I’ll put some notes into the database to tell them exactly what happened, and warn them that they have a galactic month to destroy any further batches of their nano-genocide weapon before I contact the Architects of the Shaddow Proclamation and have them subjected to the severest penalties that statute allows.”

“Good,” Rose answered. She hugged her youngest child close to her as she turned and made her way back to the TARDIS. The Doctor went to do that last, sad duty and sent the ship on its way. He set their own course for home, and it took barely a half hour before they stepped out of the TARDIS into the hallway of Mount Lœng House. The grandfather clock by stairs said it was eleven o’clock in the evening. They stepped into the drawing room and found Christopher sitting alone in an armchair with a glass of whiskey and the contents of a Dispatch box for reading matter. He looked at Rose, carrying Sarah Jane and his eyes widened in surprise. When his father explained what had happened he was even more wide eyed. He reached out and took the baby from Rose.

“You went out for an evening meal, and returned with another baby sister for me?” He laughed as Sarah Jane looked up at him with bright, wondering eyes. “Not that I’m complaining, mind. But I’m glad Jackie went to bed already. I think we’d all be glad of a night’s sleep before we have to explain this to her.”

The Doctor agreed. So did Rose.