How does a 6 year old boy know anything about gender to start with? It sounds like his parents are guilty of child abuse and now have a mentally ill little boy as a result. And modern America celebrates this sort of mental illness. Until the spotlight moves on and then he is nothing but a little boy in a skirt.
This is child abuse plain and simple. A six year old can't possibly know about his sexuality at that age. I don't think I even paid attention to girls until I hit puberty, when I was around 13 or 14 years old.
Absolutely sick and disgusting. These parents ought to be locked up and kept away from children.