Gender Determintation

A good friend of mine is due just a few days before me. They think they are having a girl, though they didn't find out for sure. Yesterday I mentioned to Jonathan that I wondered what she would do if she had a boy because she's all prepared for a girl. Emily pipes and says, "Well, they won't know for a while what it is because it won't have any hair." After stifling a laugh, I explained that length of hair is not, in fact, what determines whether someone is a girl or boy.