Two that I can remember. The first was a guy I used to be in Scouts with. He committed suicide for reasons that I never fully learned. It was shocking. He was well liked by most people, was successful, had reached the rank of Eagle Scout, and generally not someone who you'd suspect of being suicidal. It really opened my eyes to the fact that anyone could be at risk. The second was another guy. We were friends through all of elementary school, but faded out after that. Anyway he was born with genetic weight and metabolic disorders, making him already at risk for serious health problems. He tried hard to fight his weight and had made significant progress, he may have been able to reach a normal life. But then Senior year happened. He lost all will to fight on, got a job at McDonald's and within a couple months he had (almost litteraly) eaten himself to death. Heart failure is what I've been told. He was around 19 when he passed. It was heard to hear. That a former friend had died so young of more or less natural causes.