Written for a prompt on the kinkmeme:

Sherlock as a child is a complete terror especially whenever you take him to places. He really hates going to the doctor's especially and makes sure his visits leave a permanent impact. His parents get fed up over having to go to new doctors all the time because Sherlock's behavior but keep trying.

They finally go to Dr. Watson and Sherlock doesn't like him at first. But this doctor is different. He's more patient with him and listens to Sherlock instead of feign interest like everyone else. And instead of lollypops, Dr. Watson gives Sherlock a skull as a gift for being good. Sherlock likes Dr. Watson so much that he keeps seeing him, even as he grows up into adulthood. Sherlock will never have another doctor to replace him.

Zero

Even as as a newborn, Sherlock hated the nurses. He screamed bloody murder when they picked him up to change his diaper or coax him to drink from a bottle - these tasks theirs because Mrs. Holmes, though no fault of her own, had succumbed to a crippling post-natal depression. Mr. Holmes was on business in Korea and could not be reached.

These were not the normal vocalizations of a colicky child but a guttural wail so loud and so furious it seemed as if the force of it might tear the lining from his lungs. It sounded so much as if he were in pain that, despite his otherwise exemplary health, he was submitted to a battery of tests which kept him in hospital long after his mother had physically recovered.

He stilled only in his brother's arms.

Though the Mycroft was only five, the screaming was so bad that he spent most of his time propped up against the headboard in his mother's bed. His mother lay curled up in the fetal position, facing away. The ridge of her spine rubbed against Mycroft's arm. He rocked the child and whispered words too quiet for the nurses to make out.

If they'd leaned close, they would have heard him whispering, over and over again, "I love you, I love you, I'm here and I'll never go."

They would have seen that his eyes were fierce, fixed with feverish determination on the infant's wrinkled red face.