Nature most of the times overshadows nurture. I think this is a genetic behavior. That might explain why there are some men who are stronger in feminine attributes, while there are some women who are the other way around. Of course the norm for male behavior is being aggressive, while the norm for female behavior is being sensitive. And by norm, I mean the mathematical norm, which is the attribute that most people of that sex have.

Nurture might change what nature and genetic qualities dictate a person, but sooner or later when the compulsory forces are gone, individuals tend to behave according to their nature.

BTW, I remember the first photos of the twins you posted here. Your son had his arms up and was ready for a fight while he was sleeping. It was not hard to tell which one of them was the boy...