So is this the first time since lockdown that you have seen his parents?
TBH I can see where she’s coming from. While all this talk of “when can I hug my grandchildren” made me want to throw things at the tv, the truth is that many grandparents have missed their grandchildren incredibly. And children are constantly growing, whereas the adult children are, well, who they always were. Iyswim?
E.g. my eXH’s dc would have been 4 when the pandemic first hit, now he’s nearly 6. That’s a hell of a long time out of a child’s life for the adults to not see them.
I know she has seen him more recently, but I know there was a time when she didn’t, because they don’t live close.
Also, why does your MIL not see her grandchildren since the divorce? They’re your DH’s parents, so why isn’t he making more of an effort for the children to maintain a relationship with their grandparents?
While some mothers will make the effort for the kids to see the GP’s on the dad’s side (I did,) it’s not the mother’s responsibility, and I can see why his DP’s are sad if you e.g. are making more effort for your joint DC to have a relationship with them than his DC from a previous marriage, who are just as much their grandchildren.