I'm near the age group being discussed here... I think about how variable people from high school can look when they hit you up on the social networks. The "presenting" age range of people from my graduating class feels spread across about 30 years. Some people look 30s-ish, and some people have definitely lived a hard life (all sympathies for people who haven't had a kind journey).
Yep, I remember a guy at our ten year reunion, we were only twenty-eight mind you. He went from jock to George Costanza look-a-like in that short time!
One of my friends was also completely bald by 27. I'm 46 now and these past few years I've been growing a tiny bald spot at the back of my head. It's weird how big those differences are, and therefore even weirder how much we are judged by them.
