Essentially: Holmesians have long hypothesized a third, older Holmes brother who looked after the family estate and let Mycroft and Sherlock go off to London. I have this headcanon that said "other one" joined the army in his youth, served in some skirmishes in colonial Africa and came back shellshocked. The idea - which I'm not sure I really unpacked as well as I should have in the original story! - was that during the Great Hiatus Sherlock came across some Zulu Africans who were maimed by the newly-developed maxim machine gun, it forced him to confront the limit of logic in the face of violence (and passions generally), that connected with what he had seen his brother go through after his own service, and that's what makes it visceral what he'd put an old soldier through.
Anyway, I alluded to a few months where Mummy Holmes, Sherrinford, and young SHerlock went to visit the family in France, and Sherlock spent a lot of time bee-watching as a way of avoiding being around Sherrinford and people generally (since he's, you know, about seven years old at the time and in a country where he probably barely speaks the language). And it has me thinking about repression, logic and observation and deduction as a way of controlling the uncontrollable. And I think I want to write the thing.
Of course it's canon!kidlock. Is there any interest in that? If it's been written before I've never thought of it. But I'm trying not to think along those lines.