J.P.
I explain to my kids that there are appropriate ways of handling things and then there are rude ways of handing things. Just because his friend says so those doesn't mean it's ok for him to say those things. He doesn't have to like his friend sitting in his lap, but he needs to explain it, and then if that doesn't work, then mom, you can explain that some people just need more personal space.
We have nieghbors kids that call their mom a "loser" and she says nothing. My kids tried it and were sent to the naughty mat.
Remember, just because you like the mom, doesn't mean the boys need to play together. And most of this sounds like the other mom needs to handle it. We have a firend whose daughter is TWELVE...and we call her Vlecro Girl....no matter where you go, she's right there. It drives me crazy....and I send her outside to play....or somewhere. She still has issues in school with the kids.