I am trying to understand my step-nephew. I don't think he is on the "spectrum" but he has some odd behavior that mystifies me and perhaps someone can give me a clue.

He is 6 years old, in first grade. He often acts like he is a dog. It is more intense than pretending, he acts like he really wants to be a dog. It is NOT cute.

When he meets a new adult he he literally barks and pants like a puppy. He does not give up acting like a dog for an hour or more. His parents have given up asking him to not do this. He insists on buying dog treats and eats them for snacks. He also eats ants.

He seems very uncomfortable with other children and not know how to play with them. He does play nicely with his younger sister. They both dress up in girl clothes, even putting on makeup and nail polish, and play with dolls. (All his parents are sort of ok with this cross dressing.) He ignores the other family children for the most part. The other 3 kids are younger and all seem like average kids.

All the parents involved are good people. In spite of broken marriages they all get along and even go on multi-family camping trips. The main thing is the dog stuff. I think the boy has some serious issues. I am not trying to interfere with his parents, but would like to have some understanding in order to make my relationship with him more helpful.