Got home yesterday evening. I called during the afternoon to let DH know we were close - and got MIL. (At my house, while DH was at work.) Which I thought we pretty clearly decided was NOT what we would do.
When I got home, DH and I had time for a talk before going out to dinner for Babybartfast's birthday (our compromise so we didn't have to have everyone at our house). He thought he was doing exactly what we had agreed - Grandma wasn't at our house (she tagged along with FIL yesterday). I guess I should have specified "I don't want MIL and/or Grandma at the house without one of us there." It was a good talk, though, even though it was mostly me doing the talking (as usual). He didn't realize how much MIL criticizes me behind his back, and he promised to be more aware of situations like that in the future. He said I shouldn't be upset that he accepted MIL's offer of help while I was gone because I wasn't the one who would be here to deal with the kids, and I explained that wasn't the point - her "free" offer of help wasn't free because it always comes with strings later. Now she'll feel we owe her a favor, and she'll also feel that she gets more say in how we raise the girls. DH thought she was doing fine, but I pointed out that just that afternoon, MIL had told Babybartfast she could skip her nap (naps are NOT optional in our house - you don't have to sleep, but you do have to stay in your room and be quiet!) "since it's her birthday." She never mentioned that to DH and probably wouldn't have told me if I hadn't happened to call. Not surprisingly, Babybartfast tried to wheedle out of going to bed on time that evening "Since it's my birthday and I don't have to take naps anymore." Yeah, not happening.
Long story short, we're imposing a "grandparent moratorium" the week before and after Babybartfast starts kindergarten, so Babybartfast can get into her new routine and MIL can't interfere with our parenting while we're trying to nail down a new normal. DH has also promised to run every single Babybartfast-related conversation past me for a while - he really didn't understand how MIL takes his non-answers. Conversations often go
MIL: "I think Babybartfast's room needs to be pink!"
DH: "I have no opinion and am not really listening anyway. She does like pink."
And then DH goes away thinking absolutely nothing happened, while MIL goes away hearing "I now have permission to buy pink paint and new bedroom furniture for Babybartfast because my son said it's okay!" And then I end up being "the bad guy" (and have to expend the emotional energy to intervene) when she shows up with buckets of paint because DH doesn't care enough about the color of Babybartfast's room to stand up one way or the other. He's going to work on making sure she doesn't come away from any conversation with the belief that she's okay to go through with whatever thing she just randomly decided.