Chapter One: Room For One More?
"Father?"
"Yes, little one?"
"When am I getting a sibling?"
Sherlock looked up from where he was writing a paper about the effects of different acids on a variety of materials. Hamish was innocently colouring in a picture he had drawn of his family.
"What makes you ask that, H?"
Hamish glanced up curiously (usually Sherlock was quick to answer any queries he might have) and held up his drawing as way of explanation.
"Well, you have Uncle Mycroft and Daddy has Auntie Harry," his small shoulders gave a shrug, "I figured one day I'd have a brother or sister and I wanted to know if you knew when it would happen."
"Does everyone in your class at school have a brother or sister?" Sherlock asked, laughter playing around his eyes at his son's inference.
Hamish's eyebrow drew together as he tried to remember.
"No. But I'm related to you and Daddy, and I thought these things were jell-e-tic." Hamish cocked his head to the side, not quite sure if that was the word he wanted.
"Genetic?"
"Yeah! That." Hamish grinned; he had been close. Sherlock grinned back.
"Well, I promise to tell you as soon as I know if you'll have one."
"Okay."
And with that, Hamish went back to finishing his masterpiece in crayon.
When John got home that afternoon it was to find a five year old asleep on the sitting room floor and a partner typing determinedly on John's laptop in the kitchen. John smiled softly as he took in the peace and, for once, quiet of the flat while he shrugged out of his jacket.
John, always reluctant to interrupt Sherlock's work and Hamish's naps, walked quietly to put the shopping away.
"Hamish wants a sibling," Sherlock announced abruptly, not looking away from the screen. John jumped slightly, but quickly recovered (living with Sherlock had gotten him used to some surprises).
"Well, I'm not about to get pregnant, I don't care how hard you try."
Sherlock chuckled softly as he saved the progress of his research, and turned to John.
"Yes, thank you for that, Doctor. I should hope I know that much about human biology by now."
John grinned and wrapped his arms around Sherlock's neck.
"How am I supposed to know what you decide can be deleted from that genius brain of your?" He punctuated the word 'brain' with a soft tug on one of Sherlock's curls, causing the detective to tilt his head up. John took advantage of his being (slightly) taller at the moment and pressed a kiss to his partner's lips. Sherlock enjoyed the kiss for a bit and then pulled back gently.
"What are we going to tell him?"
"We'll think of something."
Over the next few months both Sherlock and John thought about what another child might mean for them, but only to themselves.
Sherlock loved Hamish more than he ever knew was possible, but then he remembered that Hamish was half John, which definitely explained a lot. But would John want to donate again? He didn't know if the world needed another biological Holmes in it, and he didn't think John needed another biological Holmes to worry about. But then again…a Holmes he could love and teach.
John loved Hamish more and more every day and wouldn't mind being a parent again, but he'd already gotten to be the biological dad, so maybe it would be Sherlock's turn. But would Sherlock even want to donate? He knew Sherlock would make a great father, he already was to Hamish. And how could John let a mind and genes like Sherlock's go to waste?
So they both pondered the question of whether they should bring another baby into the world. They both knew that they didn't have the best of relationships with their siblings, but they also knew Hamish would be an amazing older brother.
And one night, John got fed up with not knowing if Sherlock had an opinion on the matter.
"What if one of us could get pregnant?" he asked suddenly while they sat together on the couch. Mrs. Hudson had Hamish and they were winding down from last week's case.
Sherlock looked up from his book with a bemused expression.
"What do you mean?"
"I mean, what if we didn't have to go through the process of finding a suitable surrogate? What if it was just us? How many kids do you think we'd have?" John closed his laptop and put it aside (the case write-up wasn't going very well anyways) to give the conversation his whole attention.
"That depends. Would we be using protection?" Sherlock smirked and used John's newly open lap for his feet.
"That's not the point, and you know it," John grinned.
"I suppose," Sherlock started, "with how much…joy Hamish has brought us, we would've tried for a least one more."
John smiled softly at Sherlock's struggle with choosing an emotional word.
"So do we want to try for another? Or is there not room for one more in that Holmesian heart of yours."
"I think the real question is: are you willing to come in a cup again?"
A slow grin spread across John's face, one that started out happy from Sherlock's willingness to have another baby but quickly became one of mischief.
"Oh no," said John as he crawled over to kiss the father-to-be, "I think it's your turn."
And Sherlock could never refuse a mischievous John.
A/N: This technically takes place in the same parentlock universe that all of my Hamish one-shots do. However, I'm making this a separate story because I don't want to taint those with what happens in this. I won't spoil anything, but just know that this won't necessarily be a story with a happy ending.
Please don't feel like you need to read it in order to have all of the storyline in my other stories- this can be seen as completely detached from my Hamish tales. And I will do my best to post more of Hamish as well as update Rachel. Happy (or not) reading!
I figure this will be about 12 chapters long, but changes are possible. I'll do my best to update every week, most likely on Sundays. :)
Please feel free to tell me what you would like to see be included and I'll try to fit it in with my ideas. You can also guess what you think happens because I've made it quite obvious.