Well, first of all, that's very rude behaviour on the part of the boy and I'd be talking to him about it one on one and trying to figure out what he doesn't like about girls. Then I'd be having a talk with his parents. Does his Dad say chauvinistic things about girls/women? Who knows? But if you dig into the problem hope you can figure it out. I would keep encouraging the little boy to play with the girls and I think you're on the right track by getting the boys and girls to play the same games without gender differences.

I have always had the little boys play tea party and dress up and I get the girls to play cars and sports, I'll be interested to know what you figure out.