It's a long story, but ultimately FH's sister & mother don't get along. As in she wasn't invited to her daughter's wedding). FH's grandparents were upset the mother wasn't invited and his grandpa caused a scene the night before FH's sister's wedding, then didn't come to the wedding and FH had to be the one to break the news to her right before she walked down the aisle. So NOT a great situation for him and amends haven't really been made between anyone.
We just sent out our save the dates, but haven't sent the grandparent's because as it stands, FH doesn't want his grandpa there until he apologizes. Unfortunately, future MiL received hers and mentioned to the grandparents that theirs will probably be there today or tomorrow. (I had told FH to tell her the situation in advance, but you know men...) Now I'm in a sticky situation of do I send his grandma one addressed to just her?
I don't want to break his grandma's heart, but also addressing it to just her seems like I'm asking for drama.