I killed mine. And framed him for the murder of our parents. Who I also killed. I don't regret the parents. I do regret killing him. I didn't realize that he was just as screwed up by our parents as I was until I confronted him. But I'd put the plan in motion for a reason. There wasn't any way to change it without three dead bodies.
And he'd threatened my friends. If I'd left him alive, he just would have went after them.
I just had John. Well, and Coulson. But that went... bad. Apparently when you stab someone in the back even trying to make amends doesn't... do much.
I think it's whatever this place is doing. Normally I would have fudged the hell out of the details of that first story to make it sound less horrible, but I don't seem to have that option.