Hello everyone! :) This fic is an answer to a prompt on the BBC Sherlock prompt meme: I'd like to read a fic where the grudge Sherlock bears for Mycroft isn't as petty as Mycroft makes it sound. I don't want anything super-angsty, like incest or anything like that, but just some way in which Mycroft once let Sherlock down so badly that Sherlock can't bring himself to trust or forgive him.

Enjoy ^^

Rethinking the Past

"Take me with you."

How many times had he heard those words? For all that Sherlock pretended to enjoy his own company over all others, he certainly beseeched – demanded – his brother's presence often enough. But this was all wrong. Because the grey eyes had never seemed so closed off before, so cold. Like the eight-year-old boy was threatening him, but this was impossible, because he was the one with all the power here. And that was perhaps the worst thing of all.

Mycroft blinked as he left the contemplative state he had fallen to during his brother's latest diatribe on how Mycroft should just leave him alone and mind his own business. He had organised this meeting with his brother under the pretence of asking him to recover the Bruce-Parrington plans; that much he remembered. It didn't explain how they had come to address, once more, Sherlock's distaste with the measures his brother had to take to keep him safe. All the same, there was only one answer possible.

"I'm constantly concerned about you. You know that."

"I don't need your concern, brother of mine. Even less so when it comes in the form of inefficient and useless stalkers."

He'd have liked being able to justify his next words, to believe that they were part of a grand scheme meant to make Sherlock understand just how real his worry was. But truthfully they were torn unwillingly from him, bursting uncontrollably from his lips.

"You used to, though."

It was possibly the very worst thing he could have said. The slight unwinding of his brother's form that had occurred as a direct consequence of the familiar surroundings – certainly it had to be difficult for him to stay tense when engulfed in his beloved flatmate's scent, sitting in the Doctor's armchair as he was – suddenly vanished, and Sherlock automatically reached for his violin, his first layer of defence.

"Sherlock, be assured I only meant…"

His attempts at explaining himself, a task he certainly wasn't used to, were cut off by the sound of the door opening and John Watson stepping in. The Doctor blinked and raised his eyebrows, obviously surprised to find him here for what had to look like a social visit. He quickly regrouped, though, and held out his hand. Mycroft briefly shook it and watched with what definitively wasn't jealousy how John was able to get his brother to lower his bow using only a concerned look and a quick press to Sherlock's shoulder.

Surely it was time for him to depart.

"I can't, Sherlock."

"Why?" Again, this deadened tone. Again, those piercing eyes, both so similar and yet opposite to his. Mycroft was suddenly filled with a white-hot rage that was as unusual as it was unfair.

"You know why, Sherlock! You know perfectly why! Do you really want me to go through the list of the reasons why I can't once more?"

A scoff then, and that sound certainly shouldn't have come from an eight-year-old.

"What list? It's obvious to me that there's only one true reason – and that's your cowardice. Don't try and deny it, big brother. You're a coward, a FUCKING COWARD, that's all you are!"

Even then, Sherlock had known how to draw blood. But even then, Mycroft had known how to absorb and ignore hits. And so he had simply stayed silent as his brother's hands had desperately curled into the air – perhaps to grab him, perhaps to hit him, he'd never know – before shutting his (closed off definitively now, cold perhaps forever) eyes and leaving, slamming the door on his way.

The soft sound of the door shutting behind his assistant brought him back to the present, and he acknowledged with a small nod the look of slight concern she sent in his direction before holding out his hand for the pile of files she held in her arms.

It was easy to lose himself in his work; even without taking the current crisis into account, he certainly had enough to do – running a country was time-consuming, if not particularly difficult. But no matter how much he tried, he couldn't completely ignore the irritating ache of troubling memories.

Mycroft met the warm brown eyes in front of him with no surprise; of course Sherlock would have entrusted his Doctor with one of the most delicate diplomatic matters of the decade while he went off and had fun with a delusional and bored psychopath. That's just what Sherlock did.

As always, though, he felt a flash of resentment he couldn't help at the memory those eyes evoked. "So when you say you are concerned about him, you actually are concerned?" those eyes had asked then, and this question, no matter how innocently meant, certainly had barbed edges.

They started a stilted discussion about the plans and what Sherlock apparently intended to do to get them back – Mycroft's lips twitched and John reddened a little at that. Though uninformative, the chatter at least allowed him to appraise the Doctor and deduce just how close his brother and him had gotten; he was distracted from his latest observation, however, when the man gave him a bigger clue about the extent of his relationship with Sherlock than even his watch had (new and more expensive than what a man on an army pension would have bought, though not extravagant, undoubtedly a gift).

"He told me, you know." Mycroft's mouth thinned a little, his only exterior reaction to what could very well equal a bombshell in their conversation.

"Told you?"

"About what happened. Nineteen years ago." There was no doubt possible, then. This was an unexpected development. Certainly Mycroft had perceived the Doctor's curiosity regarding his relationship with his brother, but that the man had been able to ask about it – that Sherlock had actually answered him, no matter how briefly, was frankly astonishing. Still, he wasn't about to betray himself.

"I'm afraid you're going to have to be more specific, Doctor. A great many things happened then, I'm sure, and my memory isn't what it used to be."

A sharp look told him that his interlocutor wasn't fooled in the least, but John still elaborated.

"He told me…a little…about his childhood. About your childhoods. About your parents" – a ragged breath here, obviously this conversation hadn't been any more pleasant than this one was turning out to be – "and about how you had left for the university when you were fifteen. How he had wanted to come with you, and how you had refused."

Mycroft had no doubt that the Doctor had already felt uncomfortable in his presence; but for the first time since they had met, it was his turn to be unable to meet the eyes staring steadily at him across the desk. He didn't fail often. But when he did, his failures' consequences were identical to most of his decisions' – truly memorable and spectacular.

"But he also told me that you came back."

Mycroft stopped breathing for a few impossible seconds. This was data, important, unexpected data, and he had to process it. The source, first. Was it trustworthy? Everything he knew about the Doctor pointed out that he didn't lie, especially about something as important at that. So Sherlock really had told him this. But what was the context in which this information was given? Before he could ask, John continued.

"He explained how you waited a few years until you had a steady income and a safe place, until you had met 'Mummy'" – in an unconscious imitation, he pronounced the name as delicately and worshipfully as himself and Sherlock no doubt did – "before coming back to get him."

"He…My brother really told you this?" A stupid question – that's not what he had meant to ask at all. He had already determined, after all, that the Doctor wouldn't falsify facts. But John didn't seem to find this question stupid at all.

"Yes, he did. And now I'm telling you this: he needs you. Your little brother needs you."

"Explain."

The Doctor had to have known the reaction his words would provoke, because he didn't appear startled or vexed by Mycroft's abrupt answer.

"He has been receiving messages from a madman lately. Challenges. This far he has managed to stay on top, but I can't help but feel like he's in over his head."

Mycroft couldn't help but be doubtful; certainly he was aware of the texts his brother had been receiving, but he hadn't taken the threat this seriously, choosing instead to be annoyed by Sherlock's decision to concentrate on anything but his request concerning the Bruce-Parrington plans. Still, if the Doctor felt there was the need to worry, he would act.

His brain already at work, he rose and held out a hand to John, keeping the callused hand in his a second longer than necessary and meeting the surprised eyes that flew up to meet his with a piercing look most men would have found unnerving. The Doctor only smiled.

"Thank you, Doctor John Watson. I'm in your debt."

And as the other man left his office, slightly limping for a few steps before straightening, apparently consciously reminded himself he didn't need to, the slight smile that he felt floating around his features wasn't surprising – it was pretty much his default expression – but his burning eyes certainly were.

His brother hadn't forgotten; knowing Sherlock, he never would. But apparently, contrary to what he had thought, forgiveness wasn't unknown to his stubborn little brother – perhaps it was something his flatmate had taught him. And as a strange, breathy kind of giggle escaped him, most unlike him, Mycroft reflected that though it wasn't exactly the first time he'd ever been wrong, it's certainly the first time he'd ever been glad to.