Very short one from Mycroft's POV
Mycroft was sitting at his huge oak desk in his well decorated study. He hadn't chosen a single piece of the furniture in the room, except the desk, and a maximum security safe hidden behind an original Monet. He had a small stack of files open on his desk, but he wasn't reading them anymore. In fact, he was staring out of the bay window, tears fogging up his vision. Attached to the file with a paperclip was a photo of his younger brother, a year or so ago, looking as demented as he always did in photographs. Within second of getting off the phone with Sherlock, he had managed to get his hands on a copy of the file that the therapist had started on him. Phrases jumped up at the man, 'severe childhood trauma' 'abusive relationships with important male role models' 'abuse leading to addiction' 'previously admitted for twelve months for mental health as teen' 'abandoned by brother'. Abandoned. He had abandoned Sherlock. He had hurt him. He had left him alone with their father. He had allowed him to be sent to a loony bin. He had not looked for him when he'd left home. He had not taken good care of him. Mycroft put his head in his hands, his elbows leaning on the desk. He had failed. Mummy had made him promise to take care of Sherlock, to guard him and help him. But he hadn't. He just hoped it hadn't damaged either of them irreparably. He'd thought Sherlock had forgiven him, and that it was all over, but considering how quickly he'd brought it up with the psychologist showed otherwise. At least he had been to see someone. Mycroft smiled slightly. It had only taken an hour to get him to do it, because John was a huge bargaining chip. He pushed the thought away forbidding himself from thinking of the ramifications of that chip's use. He would not use his brother's only healthy relationship against him. He'd caused enough damage.