Nature/ Nurture arguement

In class on Monday, we argued the effects of nature and nurture on gender. I had the view that they both equally influenced gender, but I couldn't help but consider how I would raise my future child. I want to allow my children to play with whatever toys they choose. However, I think I would have a different feeling if my son was playing with a barbie doll (or an easy-bake oven as one classmate said). I would have the fear of him being feminine because that is still an odd thing to me, even in this age. I would predict that fathers would gear their boys even more towards masculine play because they would want their sons to be like them. If my daughter was a tom-boy and liked to play with trucks, I think I would let it go and not interfere in her play.