Sage

This is something that I've discussed extensively in my psychology and philosophy classes in college. Boys have a preclivity towards being aggressive, due in part to their hormones. However, most behavior is learned, and so the way your children are acting is probably due to the way they were brought up. Your son being around girls all the time doesn't mean he's going to act like a girl, because he is acting in response to the way he has been treated. You might not notice anyone doing it, or you doing it, but you're going to treat your son differently than your daughter, because that's the way that people tend to act. It is a very subliminal thing too, with advertising and media portraying boys one way and girls another. So your children have picked it up a lot of different places.
Most importantly, however, is now that you know they're acting different, you make sure they don't enter the realm of "girls are this way all the time, boys are that way all the time." I think that a lot of problems between the sexes could be solved if parents made the effort to teach their children that different doesn't mean diddly squat outside of the bedroom.

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