Penis Envy

I have a theory why little girls have penis envy.  I don't believe that the reason why little girls have penis envy was to bond with the father, but instead to receive affection from the mother.  They already know that they have their father wrapped around their little fingers.  Since mothers usually let little boys of the hook more easily, because "Boys will by Boys".  If they were to be a boy like their brother maybe their mother wouldn't be so strick on them.  Perhaps this is probably the reason why little girls were tomboys.