"Mycroft, where is my son?" Sherlock looked accusingly at him and Mycroft promptly forgot why he'd dropped by in the first place.

"Your s- Hamish?" He asked once he'd found his voice again.

"Yes, Hamish, your little experiment, where is he?"

"Why do you ask?"

"I am interested," Sherlock said, trying to act as disinterested as possible.

"You've never been interested before."

It was true. The boy was nearly eighteen months old and neither parent had ever shown the slightest bit of concern for the child. Mycroft supposed that was the problem with having sociopaths procreate.

"Well I am now," Sherlock snapped. "And you'd better give me an answer because you have a legal obligation to do so. I am his father."

Mycroft fiddled with the handle of his umbrella. "He is at a research facility in an undisclosed location," he said without looking up.

Sherlock threw the newspaper he was pretending to read on the floor and stood up, glaring at his brother. "A research facility? That was not part of the deal, Mycroft. You swore to me that he would have a normal childhood. You said he would be regularly monitored and assessed but that he would be treated as a normal child."

"Yes, well, that isn't what happened, is it? It would have been too difficult to control that way."

"I want to see him," Sherlock demanded.

Mycroft sighed. "Little brother, you can't see him."

"I can and I will. Or else I'll have John write about how you created a genius child and locked him up in a research facility and we wouldn't want that coming out, would we?"

Mycroft barely blinked. "Tomorrow. A car will be here at 8am."

"Thank you, brother dear. Goodbye, now," Sherlock said, waving a dismissive hand in Mycroft's general direction.

John trudged noisily up the stairs, mumbling something about Sherlock not helping him, and carrying about eight bags of groceries.

"Oh. Hello, Mycroft. Tea?" he offered, presuming Sherlock hadn't done so.

"No, thank you, John, I have to go. I expect I'll see you tomorrow." And with that, he turned on his heel and saw himself out.

"Tomorrow?" John asked as he began putting the shopping away.

"We're going to meet my son." Sherlock had sat back down and did not look up from his newspaper as he spoke.

John dropped the can he'd been holding and wheeled around, his eyebrows just about disappearing into his hairline. "I'm sorry, what?"

"Well... not exactly my son. Mycroft and his... people were trying to develop a 'super-genius'. They created the child using my genes and those of the most intelligent woman in Britain... supposedly."

"Have you ever... met him before?" John asked, trying to sound casual.

Sherlock shrugged. "No. Once he was conceived... artificially of course... I wasn't allowed to have anything to do with it. I hadn't actually put any thought into it until we were at that park the other day."

"What park?"

"We were there with Lestrade about that murder. There were children there and I… was reminded of him. I should at least have the right to see the boy."

"Yes of course. Um… What about his mother?"

"More socially inept than I am," Sherlock said. "She's practically a machine. She birthed him and took her money."

"They paid you?"

"They paid her. I didn't... Mycroft pressured me into it. I tried to delete the whole thing but it never..." He stopped and waved his hand dismissively.

"You wouldn't take the money," John said softly.

"It didn't seem right. He's a human being, John."

"Yeah," John said. "So how old is he?"

"He'd be... sixteen months next Tuesday."

"Well… I was living here then, Sherlock. Why didn't you… tell me about it?"

Sherlock waved his hand again and said, "I didn't want to talk about it."

"Do you know his name?"

Sherlock smirked. "Hamish, amusing as that seems. It was her last name. And he took my surname. Hamish Holmes."

"And where is he? Is he with a foster family or..?"

"When he was born, Mycroft promised me that he would be adopted off and that the psychologists and doctors on the project would simply monitor his progress. He swore to me that the boy would live a relatively normal life."

"So, where is he?"

"In a research facility." Sherlock glared at the wall and folded his arms. "And he will not be staying there."

"Oh..." John had almost got his head around all of this new information and returned to putting the groceries away. "Where… where will he go?"

Sherlock cleared his throat. "I don't know... I mean... If I like the child... I would be quite happy to... well... we'd have to discuss it with Mrs. Hudson of course... and only if you're comfortable with it."

"You'd want him to live here... with us?"

"Yes. But only if..."

"It's fine, Sherlock. He's your son; of course you want him to be with you. You will have to talk to Mrs. Hudson, though."

Sherlock nodded and sat still for a few moments, before jumping out of his seat and heading down the stairs.

Mrs. Hudson had waved Sherlock off with a "Yes, dear, of course that's fine. Oh, how exciting to have a little one around here. I'll have to make him something..." and now he was in his mind palace.

John went back to the shop to buy nappies, bottles, bibs, dummies, blankets and clothes. He wasn't sure what level of development this 'genius' child would be at, so simply bought for a normal sixteen-month-old.

"I could have done that," Sherlock said when John came back and showed him the shopping.

John frowned. "Oh... sorry, I just thought... You've probably got a lot of other stuff to think about."

"Yes, thank you. I wouldn't have known what to get anyway. You know I never actually said we were definitely bringing him home."

John shrugged. "Whether you want to or not, I know that as soon as I see this kid, I'm not going to want him in some institution. And we shouldn't adopt him off. You're the only person who'd understand someone like that. It'll be good for the both of you."

"Yes... thank you, John."