I saw another study about how males and females are treated from birth.They took a baby and dressed it up as a boy and had people play with it.Then dressed it as a girl and had people play with it.The result? People held and talked to the "girl" more.People set the "boy" down and encouraged it to do something..crawl..play with toy.So we still don't know what traits you are really born with and what is environmental.You have to test the differences from birth and really pay attention to how you are treating the children in ways you may not even realize! ps. to Danny my daughter use to put together new lego sets on the way home from Grandmas in the back seat of the car in the dark and be finished before we got home!!!