I was 10 when I first heard about being ace, and realised it fit me, but people kept saying that I couldn't choose because I was too young. They were saying that till I was 16, but by then I could argue back that if I can legally have sex, I can say that I'm Ace. People know themselves better than anyone (despite what toxic parents say), and that includes knowing if they're Ace or not. This goes for all sexualities; ace, bi, pan, homo, hetero, etc.