I’d not appreciate such comments especially in front of your kids and with sexual connotations and not in private intimate situations.

Can you tell him to stop?

Why is he complimenting a 3 year old on her looks? It would much better if he said how nicely she drew a picture or how well she knows her ABCs. I feel that your guy focuses too much on sexual things in women and their looks. Yours and everyone else’s. Was he raised that way?