Man...those are some rough life events. I'll say that #1 is false, because it is the saddest.
I would have rejoiced if my worst enemy was killed in an accident. And farming industrial accidents are commoner than you'd think. At least it wasn't silo gas.
When I was about 9 (and my brother 7), my Mom took us to the house of a family with a couple kids our age. The younger ones were out in the pool while my Mom and I were inside visiting with the parents (I think I was actually watching Astro-Boy on their TV). My brother's friend Daniel came sprinting inside, yelling "Mum! Mum, Scott's drowning! He's at the bottom of the pool and isn't moving!"
The whole house emptied into the back yard, behind my Mom who was in her E.R. nurse-urgent-but-composed-but-terribly-concerned full flight while the kid's mother dialled whatever the equivalent of 911 was there. We fanned out around the pool, searching for my brother in the depths when suddenly it became apparent that Daniel thought he was being funny: all cracking up and pointing at my brother sitting a dozen yards away in the sandbox looking puzzled.
We left early that day. I'm sure Daniel still bears signs of his mother's wrath.
I was actually a little traumatized by the death of my enemy. I had something of a survivor complex over it - wishing the kid dead, then coming to school one day and finding out he is. I don't think I've hated anyone that deeply since. You bind up all sorts of your own identity in a really negative way when you deeply hate someone.
I was kind of reborn by the wheat-bin incident. A (different) family friend had a huge station at the edge of the Outback in Moree, NSW. I spent a summer with him and his wife when I was 11. I owe my life to him, since it was my own stupidity that put me under the wheat. I have no idea how he found me, nor where he got the strength to haul me out from under it by a single hand around my ankle. I spent 2 weeks in the hospital, as it turns out ingesting raw wheat is quite dangerous. The tiny hairs on the grains can enable them to bore into your tissue.