My son wants a vagina

My 4 year old son loves to dress up as a girl.  He plays w/ both boys and girls in school and in the park.  My wife and I let him dress up however he wants at home and during play time at school.  But we insist that when going in public he dress as a boy.  Recently he asked my wife if she could cut off his penis and make him a girl.
I notice that when away from his mother, to whom is VERY attached, these desires dwindle.
What should we do?  Is this a definitive sign of a transgender child?

daddy510

[Kevin Kennedy, Ph.D.]

It is too early to know about that, but it is true that some children at a very young age become aware of gender difficulties. They are literally uncomfortable in their own bodies. It sounds like you and his mother are handling the situation well, being supportive and yet realistic at the same time (e.g., by having hinm dress as a boy in public).