How would you feel if your partners friends said stuff like this?

My partner and I have a beautiful 9 month old baby and whenever we are around his friends they all making these comments and I’m starting to get so sick of it.

They says things to my partner like “are you sure he’s your kid” “is he the mail mans kid” “aren’t you happy he takes after his mummy?”. My partner doesn’t really say anything when they make these comments but I’m sure they’re upsetting especially when he hears them often. And it’s really starting to bother me. They constantly degrade him because of his looks. He’s a red head, is losing his hair and already has some body issues but they make fun of those things as well.

I can’t stand people that make jokes about others appearance’s especially when it’s something you can’t change.