When they reached Torchwood, they immediately found Jack hard at work in front of a computer, trying to keep Ianto from goofing off too much. The Doctor had to shout to get his attention.
"Jack! Over here!" He waved one arm with the other on the stroller.
Jack told Gwen to make sure that Ianto worked while he went up to greet both his friends with hugs. He then crouched down to look at the red-headed, brown-eyed baby in the stroller.
"Who's this little guy?" He asked.
"That's our son, David Tyler Smith," Rose told him.
"When did you get pregnant? I know it's been a while since I've seen you, but I think I would have remembered if you ever told me you were expecting," Jack replied, a little surprised.
"No, we found him outside the TARDIS. Someone left him outside there with a note that asked us to take care of him. What's even more unusual is that the baby is part Time Lord,"
"But that's not why you're here, is it?" the head of Torchwood looked up at friends and asked while their son gripped Jack's index finger.
"No, it's because we'd like to know if you'd like to be David's godfather," the Doctor explained.
"Sure, I'd be honored," he said with a smile before asking if he could hold his godson.
"Yeah, be careful," Rose told him as she bent forward to undo the straps holding David in the stroller. Jack held the now-sleeping baby, smiled at him, and kissed his forehead.
"He's a cute little guy. Something tells me he's going to take after his old man, and I'm talking about the man standing in front of me," Jack told the new parents, which got them both to smile.
Ianto and Gwen then walked over to see the baby. They both smiled as they gazed down at the small bundle of joy wrapped in the blue blanket.
"This is the Doctor and Rose's baby, and my godson, David," he introduced the baby to his team. They smiled at the sleeping child, talked about how cute he was, and asked how old he was.
"How old is he?" Jack asked the new parents.
"A newborn. Ten days at the most," the Doctor explained, "I know, it's not every day that you find a baby in a stroller on a sidewalk in Cardiff."
"Even more so outside of a space ship," Rose added, "Anyway, we should get going, and tell Donna that she's the godmother-"
"Oh, I'd be more than happy to tell her," Jack told her, handing the baby back, "she's going to be thrilled."
"-and my mum that she's a grandmother. She's going to go nuts."
"Yeah, tell your mum," the Doctor groaned as he started to push the stroller. They said their goodbyes to everyone at Torchwood, and made their way to the TARDIS, where the Doctor dreaded the trip to Powell Estates.
The Doctor and Rose took a deep breath as they opened the door to Jackie's flat. Jackie immediately hugged and kissed everyone and stopped when she saw the baby in the stroller.
"Who is this?" She immediately asked when she saw David and smiled big.
"Well, that's what we wanted to talk to you about. Let's sit down and talk," Rose said as they went into the living room. The Doctor sat nervously next to Rose as she took David out of the stroller and Jackie sat in the easy chair.
"Just so you know, the baby is part Time Lord, but not our biological son," the Doctor told her, attempting to avoid a slap.
"Your son? What do you mean, your son? He's your child now?" She asked, surprised.
"For all intents and purposes, yes, he is our child. Someone left a note on him asking us to take care of him, and that they couldn't. When we found out he was part Time Lord, we kind of figured out why."
"So how did you find him? Did he just show up outside the TARDIS?" Jackie asked.
"Actually, yes, that's exactly how it happened while we were in Cardiff. I saw him, and brought him inside. The Doctor looked him over, we got a few things for him, and we're here, introducing him to you," Rose explained.
"What's his name?" the new grandmother asked.
"David Tyler Smith," the Doctor told her, offering the baby. Jackie gladly accepted the blue blanket-wrapped child and smiled.
"He's an adorable little guy. My beautiful little grandson," she said, kissing his forehead and rocking him a little. "How old is he?"
"Newborn, less than ten days, we think," Rose told her.
Just then, they heard a knock on the door. It was Donna, the baby's godmother. She had a bag of clothes and a couple of toys for David. There were plenty of sleepers (including a West Totthenham outfit), a multitude of onesies, a few pacifiers, stuffed animals, teething toys, and a rattle.
"Thank you so much," Rose said with surprise.
"Of course. I want to make sure my godson has a few things," she said. Donna then took the baby in her arms and grinned broadly.
"Oh, he's a little ginger. Jack didn't tell me that," she mentioned.
"Don't remind me," the Doctor mumbled bitterly. This got everyone else in the room to laugh. A few minutes later, Donna checked her watched and said that she should probably leave and was ready to hand David back.
"All right," the Doctor sighed, "I'll see you later. Thank you so much for everything," he said, taking the baby and hugging her. Rose hugged her as well, and told Jackie that it was nice to finally meet her.
The Doctor said he was going to feed and change the baby before dinner. Jackie took this as a chance to talk to him about what he planned to do about traveling and caring for the baby.
"I want to know if you plan to carry on travelling or if you plan to "go domestic", as you call it," Jackie asked.
The Doctor sighed as he burped David and laid him on Rose's bed to change his diaper. "I honestly don't know. Rose and I are going to talk about this in the morning. I assure you that whatever we do will be in David's best interests."
"It better be. This is my grandchild we're talking about," Jackie warned him, giving him a look that said that if they didn't, he'll be slapped into the 52nd century.
The Doctor nodded nervously as he changed his son's diaper. Once he fastened the boy's onesie and blue outfit and lifted him up, the Doctor discarded the soiled diaper in the bathroom waste basket and put the wipes back in the diaper bag. He then laid David on the couch.
The three adults enjoyed a dinner of shepherd's pie and chatted about what had been going on since they had last seen each other. Every so often, he and Rose would look over to the baby looking up at the ceiling. They were both amazed at how many lives he had changed in such a short period of time. They wondered how many more and how much he would continue to in the years to come.
Once they got back to the TARDIS, they set up a little nursery with the cradle and a makeshift changing table/dresser from a desk the Doctor almost never used. They put the new clothes and a few diapers in the drawers and the container of wipes on the table. The walls were plain white for the time being, but they hung some Winnie the Pooh decorations that Jackie still had from when Rose was a baby. The Doctor and Rose gave him a sponge bath (Jackie and the Doctor told her not to give him a real bath until his umbilical cord fell off), fed, and changed David one last time before putting him to bed.