Reynolds was from Florida. With so much of the industry based in Cali, a bunch of guys based in SF or So-Cal became pros pretty young. Carroll was 17 when Girl was started and had been pro for like 4 or 5 years at that point. No one ever expected this longevity. Carroll is two years older than Reynolds though, but Reynolds wasn't a big name until like 97, while at that point Carroll had been a big name pro for like 6 years. Chico is the same age as Reynolds.
I think Rickk was the oldest of the people who started Girl, and he was 19 or so.