One of my longest fics (Gifted Children) is a fusion of The Gift about an older sibling's conflation of heroism with suicidality. As much as Simon is grateful for having the chance to, in some sense, save River, it's also something he can't help failing at, and the only way he can quit the job is by dying. So even though it would bother *me* a lot more if Simon died, it's really a lot more painful when Wash does because as far as he's concerned he could happily be Zoe's husband and Serenity's pilot forever.