Does your five-year-old boy have gender issues if he has always been interested in girls' toys and likes to dress up in girls' clothes?
Many young boys will dress up in girl's clothing. My brother use to be the model for my mom when she was making my skirts for square dancing and he wouldn't let her do it until he could twirl in it! He is much older now and is married with 2 sons. It is a possibility that you son may have traces of gender issues and it wouldn't hurt to take him to a child psychologist while this young. The older he gets the worse it may get. As you know young children are very impressionable and if he has been hanging around with sisters or a family with mostly women and young girls that may make him want to dress like a girl to fit in. See a professional about this just to put your mind at ease.