Different tails?

[eenie114]

Recently, my broody hatched 2 chicks. They're about two and a half weeks old now. There is one white one, and one black. The white one's tail sort of slopes downward, and the black one's tail sticks up a lot more. The black one also has a larger comb. Mom is a Buff Orp and Dad is a mix, but he has some Frizzle in him. Am I correct in guessing the white one is a girl, and the black one is a boy? Or is it too early to tell? Sorry I'm not able to post pictures right now, camera died.

Thanks!