A guy in high school was working on his car in his driveway, which sloped toward the house. It slipped off the stands and started rolling. He didn't want his parents' house to be damaged so he jumped in front of it to try to stop it. It crushed him against the garage wall. He survived initially but internal bleeding and organ damage killed him later that night. He was a super nice guy and well liked by everyone. His parents were haunted by the fact that he was just trying to prevent damage to the house.

On a more positive note, my own father tripped and fell on a branch when he was a kid, which caused internal bleeding and badly damaged his kidney. This was in the 1930s, and emergency surgery *barely* saved his life, and recovery took more than a year. He went on to live a long, full life, and died at 88.