I remember reading about monkeys being observed after given stereotypical children's toys.
The juvenile male monkeys chose to play more often with the boys toys, and the females chose more often to play with girls toys, although the difference was less pronounced in the females
Seems preferences are heavily affected by biology
If you wouldn't discourage a daughter from liking tractors, and even encourage that, isn't it sexist to *not* encourage your son to like whatever he gravitates to?
The juvenile male monkeys chose to play more often with the boys toys, and the females chose more often to play with girls toys, although the difference was less pronounced in the females
Seems preferences are heavily affected by biology