My DP doesn’t have children of his own, but gets along well with my two (17 and 19 respectively).
The issue is, he often puts his foot in it with comments and then blames the fact he has never had DC himself so isn’t used to what can and can’t be said.
It isn’t anything extreme as such, the latest example is my DS1 having friends over yesterday (all 16/17) and DP asked one his age, acted surprised and said he must have done a paper round in a warzone.
My eldest has a holiday abroad coming up, when DP was told about it he said something about stocking up on condoms and to get a league table put up in their accommodation. They aren’t going to a party resort and aren’t that type of group.
He is great aside from this but it’s starting to cause me some embarrassment.