Gray Castles

Sherlock stared down at the bundle in his arms. Warm. Alive. Bright blue eyes stared at him curiously.
"His name's Hamish."
"Your idea, I expect, Mary."
"Completely her idea." John replied. He hated his middle name with a passion, but on this little bundle of joy, the name seemed to fit. "Hamish Sherlock Watson."
Sherlock froze. He'd been swaying back and forth almost instinctively. Then, Hamish began to cry.

Flustered, Sherlock tried to hand him back to Mary. "Why-why is he doing that? What-did...did I do something wrong?" Mary laughed.
"Nothing wrong, Sherlock. He's just a baby, babies cry."
"It's horrific."
"Get used to it. You're babysitting." Sherlock's head shot up, his eyes wide.
"What?"
__________________

An hour later, Sherlock figured out how to make a bottle by looking it up and Hamish was asleep in his arms. He scrambled for his phone when it began to ring and he answered it.
"How are things going?" Mary asked.
"Fine. Fine. Just...one problem."
"You didn't lose my baby, did you?"
"I can't put the bloody thing down!" He whined. Mary laughed and hung up just as John walked through the front door of the flat.
When John took Hamish from Sherlock, the baby woke and watched Sherlock, cooing, but when Hamish realized he wasn't in Sherlock's arms, he began to bawl.
When Hamish and John left, after Sherlock had said his goodbyes to the little one, Sherlock began talking to his skull again.

".....I want one..."