My second generation "boy" has turned into a girl! It still says boy in the info page but it is definitely a girl, with curly hair and a big, big smile.
It does not matter what it looks like, it's a boy. A tamas gender never changes and it really does not make any difference at all as to your charecter you get unless your tama is still a baby, or an elder.
P.S. it sounds like you have a memetchi. does it look like this... ?