my recently divorced boyfriend’s son (who has autism) always asks for “mommy’s house” - need advice

hi everyone.my boyfriend separated from his wife last year, but it had been rocky for quite a while before that. my boyfriend’s 6 year old son has autism, and I would say has limited verbal communication. he’s amazing and sweet and smart, but one thing that has been really hurting my boyfriend recently is that he always asks for “mommy’s house”.we’re not really sure why to be honest.. my bf is VERY kind to him, he’s super involved, plays with him, etc. but he still asks for mommy’s house basically every time he has him (3-4 nights a week). usually it’s after he doesn’t get something he wants, like when it’s time for no more screen or he sees a park and can’t go to it.basically I’m just looking for advice. it hurts to see my boyfriend hurt, and I just want his kiddo to be excited about daddy’s house. I’m terrified that he gets anxious at his house but can’t communicate it verbally, or that he is going to become super withdrawn from my boyfriend. maybe someone has experience with a child preferring one parent after a separation/divorce? any advice or insight would be greatly appreciated!EDIT: spelling error via /r/Parenting https://ift.tt/2qkgLN2