10.
Mycroft knew enough of what it meant to be normal to know he was not that. He could read people within seconds of meeting them but he did not completely understand them. He knew himself to be manipulative and lazy, and did not understand why he did not completely despise Sherlock. Every book he read on the subject indicated it was normal to feel resentment towards his brother, for being needy, for being a disruption, for making him devote time and worry and care when he could be doing something he enjoyed. And yes, as children, they had their arguments and fights as all brothers did. Sometimes Mycroft would want to read and Sherlock would want to play. Sherlock could be invasive, getting into his things without permission, taking things apart to see how they worked, breaking them.
He was also the closest thing to a peer Mycroft had. Sherlock had the same sort of mind that could read the world. Even as a toddler, Mycroft could feel the spark of a connection. And the age gap was enough that Mycroft didn't feel displaced in his parent's affections; he felt grown up. He had always felt a bit more grown up than most adults allowed for, and for the first time he was treated a bit closer to how he saw himself. So they fought on occasion, of course they fought, but most of the time Mycroft could allow for his little brother's eccentricities. Because he understood.
He didn't resent his brother then, and he didn't resent him for making him worry or care or the fact that he dragged Mycroft out of the comfortable shadows and made him move. At the age of sixteen, if he had had no brother, he would have spent the time without ambition, with no real goal except to read the world and let it go on as it would. But he did have a brother. And so he breezed through classes with very little effort while devoting his study times to a mixture of psychology, languages, and communications, and every weekend and many afternoons, he would leave school and visit a small but expensive institution or the London flat his parent's kept. He wasn't going to see his parents however, though they were often there on the weekends. He was going to see Sherlock.
Sherlock who hadn't spoken a single word in nearly two years.
The institution called itself a school, and in fact did have lessons like any normal school might. But it also had doctors and therapists and some of those lessons involved basic life skills or peer relations. Sherlock hated it there. He didn't say it, of course, but Mycroft could read it in his eyes. Sherlock might not talk, maybe he couldn't talk, but the intelligence was still there. He wasn't lost in his own world, no matter what the others thought. He saw this world far too clearly, and he wanted no part in it.
"You're being stubborn," Mycroft told him when he visited. And in an almost childish hope, particularly for a person such as Mycroft, he set about teaching his brother things the school saw no need for. They tried to get him to talk, or at least respond, to paint or play music. Mycroft thought it was quite ridiculous the way they treated his brother, as though the incident when he was seven had given him brain damage. And Sherlock was stubborn. He knew how to play the piano and the violin, but he acted as though he could not read a note and the only music he played was guided by his instructor. Left to himself, he pounded viciously on the piano in violent discord. Mycroft thought that evidence enough that his brother could communicate when he wished to.
Mycroft never talked down to him like his teachers did. He didn't talk at him either, as Mummy tended to do, and he didn't lose his patience and have to leave the room like father. He sat with him, until Sherlock would suffer the inactivity no more, and he taught him. Sign language was the first method he thought of, back at the beginning before he was sent to the institute when they still hoped he would snap out of it. It was highly encouraged by everyone. They weren't sure if Sherlock wouldn't speak or if he just couldn't. Sherlock himself gave no sign that he understood why Mycroft was making his hands into shapes, and he showed no interest of doing it on his own. Mycroft kept at it anyway, using his mind for the first time to really learn something, not just reading whatever came at hand and seemed interesting, but actually being interested. And to all appearances, Sherlock made no effort and learned nothing.
He did look though. Like a sphinx whose eyes took in everything and gave nothing back, Sherlock watched the world. When Mycroft had more or less conquered the new language, and had shared all he knew, he went on to other ideas. Nobody praised him anymore for trying to communicate with Sherlock. They seemed worried at Mycroft's near obsession with his brother, as though he was losing his friends and his own life over it. Mycroft knew that was ridiculous. He knew what a friend was, and no matter what his peers liked to think he'd never had one of those. His peers followed him whether he spent his free time with them or not. As for his life, Sherlock gave him a direction and purpose he'd lacked before. More than that, his little brother presented himself as a puzzle. True, it was a puzzle Mycroft held a great deal of love and care for, but that only made it more interesting and vital that he solved it.
He tried codes next. Sherlock was, in some ways, very like Mycroft. He couldn't resist puzzles. So whenever Mycroft had to leave him, and they made him leave in the end, back to school and eventually Sherlock to the institute, he'd leave him puzzles to solve. Sherlock studied them, sitting still and silent and never picking up a pen, until he apparently got bored of each and tossed them aside. He looked as incommunicable as ever.
By the time he was sixteen, Mycroft's routine was well established. He went to school, did just enough work to get top marks and keep his network of students and teachers in place, and spent the rest of his time devoted to Sherlock. Perhaps it wasn't the healthiest way to live, but at least he was alive.
He always went home for holidays. Sherlock went home as well, and the entire family made an effort to pretend they had been splintered two years before. Mycroft studied Sherlock's condition, looked over the psychiatric notes which he wasn't supposed to really know about, and continued to teach Sherlock different ways to communicate in the hopes that one day, when he was ready to respond, he'd have a way, even if his voice failed him. He also simply read to him. Sherlock seemed to enjoy it, and Mycroft knew the lessons the institute tried to teach him weren't nearly challenging enough for someone of his brother's intellect. The problem was, it was very difficult to convince anyone just how intelligent Sherlock really was. He read him all the books Mycroft used to read when he was his age, and anything else that was lying about, like the newspaper or Mycroft's newest book on ciphers.
Mycroft was reading the newspaper when he came across the article on the drowning. He didn't read it to Sherlock. One did not talk about swimming to Sherlock, or try to get him near a pool; he had reacted very badly whenever the therapists had tried and went into one of his darker moods where he refused all interaction at all. He did hesitate, perhaps a bit too long. Sherlock watched him, silent and waiting. Then Mummy took him to sit with her on the piano bench, hoping to convince him to play with her. Sometimes he would, and sometimes he wouldn't. He never would with the music therapists, pretending to not even know how. Mycroft forgot about the article. Sherlock apparently didn't.
Mycroft found him later, the paper retrieved from the rubbish where he had left it. Sherlock didn't look like he was reading it so much as he was studying it, like it was one of his experiments. He looked up when Mycroft came in. They were both silent, Mycroft wary and Sherlock expressionless.
"This is wrong."
Nobody listened to a nine year old boy or his sixteen year old brother. The world saw two children trying to tell adults trained in investigations that they were wrong. Their father saw a boy who survived a traumatic event, now obsessing over a similar accident. Their mother saw needless conflict over a tragedy she did not want to think about.
Mycroft saw that the world would not accept his brother. Sherlock wasn't like him. He needed to touch the world. Sherlock, at age nine, rejoined the world and found it lacking. He became determined that he would become big enough to be listened to, and he would make them listen. He would solve their crimes.
If Mycroft had been an only child, he probably would not have bothered with the world at large, preferring his own comfortable corner where he could read at his leisure do as he liked. But he was not an only child. And if the world wasn't going to accept Sherlock, well, he decided he would have to change the world. If the world was unjust, he would make it be just. And if he had to leave his comfortable little corner and actually move every once in a while, well, for all that he had taught his brother, Sherlock had been teaching him too. Sometimes, a little bit of discomfort could be worth it in the end.
"This is wrong." The first words spoken in two years, barely more than a whisper. If he were a different sort, Mycroft would be jumping up and down, whooping and celebrating. He stared at his brother.
"Tell me why."