We are not really sure the age or the sex of our RIR but we have been looking for more info on them. We have one that is a little behind the rest. We was told they all should be female but from what we have read they say its a boy or its dying. The rest have tail feathers but she don't. Should I be worried? We have had them almost 4 weeks now. The store we got them from really didnt tell us much about them or how old they was when we got them.