Again, major thanks to all those who read and reviewed, especially reddwarfaddict, Cute Gallifreyan and Shrink to Be for reviewing both chapters. Nice to see you guys like this stuff, so here's more!

Chapter 2

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"So, where did the baby come from?"

"Well, to cut a long story short: the Doctor had an accident with the machinery at the labs- you saw what it can do- and got turned into this. Well, to cut a long story short anyway." She doubted Tish had really been listening, instead choosing to gaze at the tiny figure of the Doctor playing with the toys around his basket. "Tish?"

"I heard." She shook her head "I just… I know it can make an adult younger, but to reverse everything? Change someone back to a baby?"

"Seems possible. After all," She cast the Doctor a significant glance and he finally seemed to notice someone was looking at him. As he turned to look at her, his mouth opened in a huge smile and he reached out his arms. Martha grinned back, obliging to his unspoken request. "You alright?" She asked softly, cradling him.

"Can I…?" Tish asked hesitantly. Martha looked up.

"Hold him? Course." She handed the baby to her sister, who took him gently. The instant he was in her arms, however, he howled and Martha had to take him back. "Sorry." She murmured as the Doctor calmed. "There was no need to be rude- it's only my sister, see?" Martha admonished him, holding him up. Tish waved as Martha returned him to his basket.

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Jack heard the women talking and changed his mind about returning to the kitchen. He had fought countless aliens, he had been killed more times than he cared to remember, but he did not do domestic. Especially not when there was a baby involved. Instead, he turned towards the console room, leaving the women to their own devices and praying to whatever deity existed for the Doctor to emerge relatively unscathed.

About an hour later, he watched as Martha's sister left. Having waved goodbye (and waved the Doctor's chubby fist too), Martha turned on Jack.

"Where were you?"

"Changing. He puked on me, remember?"

"It doesn't take an hour to change. And I seriously doubt you changed in here." Jack was about to reply when he saw the Doctor looking thoroughly upset. He was about to point it out to Martha, but she followed his eyes before he had to. "Oh sweetheart, what's wrong?" Jack raised an eyebrow at her, highly doubting she would have called the Doctor that, or anything like it, were he in his usual state. Ignoring the ex-Time Agent, Martha checked the baby over. "Tish just fed you, so you can't be hungry. I'd smell a nappy change need…" Jack couldn't resist a small chuckle. The Doctor, saviour of the universe, needing his nappy changed? The thought was hilarious, and even Martha had to laugh, although she tried to glare. Jack saw her tiredness.

"When was the last time you got some rest?" He asked. She put her head to one side.

"I was asleep when you came in."

"According to the footage I saw, you only got back with him about ten minutes before that. And that was getting back from killing a monster, destroying his lab…" Martha gave in.

"Fine. Here." She handed the Doctor to Jack before heading for the door. As she opened it, she turned. "And if you harm one hair on his head, I swear…" Jack shook his head at her.

"I'm kind of hard to kill, Martha. Get some sleep."

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Martha woke up, half-expecting to see the Doctor in the crib next to her. After a brief moment of panic when she realised he wasn't, she remembered that Jack was looking after him. She pulled on a dressing gown and went to look for him.

He sat on the floor of the 'nursery'. The Doctor was in his lap, giggling delightedly as he dangled various toys over his head. Martha leant against the doorframe, smiling at the sight. Jack had never struck her as someone who was that good with babies, yet here he was, playing with one quite contentedly. The Doctor managed to grasp a small rattle and Martha chuckled as he tried to 'wrestle' it off the ex-Time Agent, who laughed and put up a mock resistance. Finally, the rattle was yanked from his grasp. The Doctor squealed in triumph, instantly stuffing the toy in his mouth as Jack looked up.

"Kinda cute, isn't he?" Martha shook her head slightly.

"I know you've only been around a bit, but I never would've thought you'd say something like that." Jack shrugged.

"Normal babies are boring, but when it's the Doctor… well, I suppose a good reason for looking after him is just for the ammo when he gets back to normal." He grinned cheekily as Martha laughed.

"Yes, it'll be funny when he tries to get all superior on us. Bit hard to do to someone who's changed your nappies!" Jack shared in her mirth and they laughed together until the Doctor, either bored with the rattle or deciding he wasn't getting enough attention, threw the freshly-gummed toy at Jack. It hit his nose, covering his face in baby slobber. Martha was in fits of laughter as Jack glared down at the baby in his lap.

"You wait until you're normal…" He muttered. Martha suddenly realised what he was saying.

"You mean, he can turn back?" Jack looked at her as though it was obvious.

"Yeah. Why not? Torchwood's in control of what's left of the lab, they arrived just after you left. All I need to do is persuade them that they want to give me the machinery and I'm sure I can get it fixed."

"You're sure?"

"Well, fairly sure. The Doctor could definitely do it if he were normal, but if he was, then we probably wouldn't need it anyway."

"Yeah, we'd probably be off on some space station or something by now. Well, me and him anyway." Jack nodded.

"Very probably. Anyway, we've sorted out what we're going to do, so let's start now." He nodded at the Doctor "You'll need to take him back though." Martha shrugged.

"Fine by me." She stepped over and gently lifted the baby, who cooed happily as he was raised. Jack got to his feet. "You'll probably want to wash that stuff off your face though. And you," She told the Doctor "Need to sleep for a bit. C'mon."

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Jack, all traces of baby contact washed away, strode out of the TARDIS and headed towards what had been Dr Lazarus's Laboratories. The building was sealed off, but a quick flash of his Torchwood ID was enough to get him inside. As he strode into the main hall, he noticed some familiar faces.

"Owen! Tosh!" The pair looked up as he bounded over to them. "What are you doing here?"

"Somethin' to do with the fact that we've dealt with more aliens than any other department recently, so they reckon we're the most qualified." Jack nodded and headed over to the capsule which stood on the dais in the centre of the room.

"Careful- we think it's still active." Tosh cautioned him.

"It is," He told her, cautiously approaching the cylinder. He had found the sonic screwdriver in the bundle of clothes the Doctor had been wearing when he had his… accident, which helped enormously as he scanned the machinery. "What we need is for this to work, just once, but to age someone instead of de-aging them." He told his friends above the whine of the screwdriver.

"Why?" Asked Owen.

"Trust me, it's a long story." Jack told him, sealing two wires together with a quick press of a button. He looked round to see them staring at him. "What are you waiting for? Get this thing working!"

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Having been fed and bathed, a warm and drowsy Doctor lay in the cradle as Martha watched. Music stole into the room, a lullaby in a language she didn't understand. She expected it sounded better that way- as the words, despite being unknown, were hauntingly beautiful as they lulled the baby next to her into a peaceful sleep. Martha smiled down at him. He looked so adorable lying there amidst the blankets and the teddy bear she had added (originally just for the fun of it, but the Doctor seemed to like it being there). It was hard to believe that this tiny thing had faced so many dangers, had come so close to death so often, had had so many emotions flitting everywhere. Yet it was true. He was still the Doctor, lying there with his memories now buried in Martha's mind. She refused to touch them, half out of reverence for her friend, and half because the emotions they brought were so powerful- the only time she had allowed them to her conscious mind was that morning in the lab, when the Doctor had been transformed. She mentally shook herself. She didn't want to think about it.

The song quietly drove the memories from her mind and, despite the fact that she'd slept for a few hours previously, Martha allowed sleep to claim her once more.

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