the problem with two psych majors under one roof

Overheard while washing dishes last night.

M: Daddy, do you have a pen*is?
J: (pause) Yes baby, I do.
M: Why?
J: Because I am a boy. You and mommy are girls so you don't have a pen*is. You have vagina*s instead.
M: Why?
J: (longer pausing) because we are made differently, boys and girls. (another pause where I can feel the wheels turning from the other room) But you know, some people aren't born in the right bodies. Some boys are born in boys bodies and wish they were girls and some girls are born in girls bodies and wish they were boys. It's called gender identity disorder. I have a friend at work who...
M: Let's play airplane!