Eh... I think that depends on why my son didn't get along with them. My son gets along with everybody. His girlfriend's family loves him. If he didn't like them, there would probably be good cause for it. Chances are, I would have issues with them for the same reason he did. That being said, I would keep the peace and stay out of their affairs regardless.
Me liking anyone has nothing to do with whether someone else likes them. My daughter loved her inlaws, seemingly. In time she came 'round to her senses about, not just the inlaws, but in her choice of husband. That is history now. I never made friends with those people. I'm not a hypocrite and don't hang with people I don't like. They thought I was a snob. I am.
My two oldest kids live in two different cities a great distance from me. I got them launched on year ago and only met their inlaws then and for a brief while.
If they have a problem it is their to solve, not mine. Their in-laws seem like fine people and on meeting we got along with them fine. IMO there is really no need for any contact except in future cursory social events. Even if I did not like them I would behave and not let on. One never knows when their actions will come to bite them in the ass, so I tend to be polite. Period
Pearl 