Have extended family that is gay and for what ever reason after a couple of decades of everyone knowing or realizing what was going on it is causing more problems now than 10-20 years ago. One of the parents always has and does try to disguise the relationship. I was interrupted from introducing the partner at a social event when the parent jumped in saying this a friend of the family. The parent and gay adult child are fighting like teenagers and parents to the point of not speaking. And the parent still tries to disguise or misrepresent the adult child's relationship. The funny thing is they seem to like the partner or at least act the part but they refuse to admit outside of family what is going on. Not a topic of discussion. Nor that you need or had a big political, moral or religious discussion/announcement but the partner is still talked about as a "good" friend or friend of the family. You would think by the time everyone had gray hair no one would want to argue but decades of suppressed feelings, grudges what ever have boiled to the surface now when socially acceptable is in.
I think when all their friends are talking about their kids and grandkids and they aren't my guess is that was a zinger used during a routine argument because "grand children" or lack there of has been slipped in many times at family social gatherings especially.