Oh, boy. Here he was expecting the variant on 'why can't grandpa come back?' He wasn't sure he could give much advice on absolution; his mother might be a better person, but she wasn't here.
"It's not really a formula. Some of it is remembering that they died. On the planet I come from, you burn a funeral offering for your enemies as well as your friends. The superstition was so their ghosts won't haunt you, but ghosts don't have to be real spirits." He wondered if the girl would understand that; Miles wasn't sure he got it until he was seventeen and accidentally dragged Elena and Bothari into a war zone.
"Other than that," Miles looked at his hands, "you try to do something." He tried to think of an example. "If it was in a war, you might work hard for peace. Things like that. Learn from it, and try to make the universe less of a place where things like that happen."