Story help!!!! about a characters past!!?

it's starts off when the character is a little boy and he's a kinda vague, dreamy boy. he has white-blond, shaggy hair, tanned skin, grey eyes and an innocent and cute look about him. his name is keenan. whenever he's with friends he still feels lonely. even before his teengae years he's turning into a rebel that's always getting in trouble with the law. he doesn't fit in with his family (even his looks are totally different to his brown eyed and brown hair mum, dad, brother and sister). but why did he change from being sweet and innocent to a bad boy??? he's a teenager now.