I am working on getting back a story list lost to a failed HD. This should be an easy one but I just cant pull it up from my memory. It's from the do-over grp.
The guy wakes up in his younger self and his sister is not dead yet. he decides if nothing else he will keep her from being killed on graduation night in a car wreck so he tells her enough to keep her alive. but Fate keeps trying to kill her using the same or nearly the same situation.