MIL driving me bonkers. (Sorry.)

[GoingToNameChangeForThis]

I've name-changed as I never usually post personal stuff on here, only trivial shit!
I'm posting though as I generally want to know if IABU or not (not posting in that board, I'm too chicken.)
Basically, MIL completely going over our heads whenever we say something, If eg, she says "what are you doing for tea tonight?" and we say we've got tea covered and we're doing sausage casserole or whatever, she'll speak loudly so the kids can hear "Oh, but we could go to KFC?"
Then it's US who look like the bad guys when we have to calm the "YAY, KFC'S!" or whatever she's said out loud and say we'll do it another day.
She does it with other stuff too. Mentions things in front of the kids what we can do before we've said whether we can or not.
We go on lots of days out and stuff with her. Is it too much to ask be able to ASK us first whether we can before saying it in front of the kids and getting their hopes up?

Tell her then

I try! She still does it though!!

Tell h to. Keep reminding her

Get all PA on her. "Oh what a shame grandma mentioned KFC when she knows very well we're having sausage casserole. You got so excited, only to be disappointed. That was silly of grand ma, wasn't it? Never mind, she means well. There there, don't cry..."

I actually can't imagine anyone doing this and I never would, but I think it would be hilarious! (Sorry, not helpful)

haha definitely do what Coughie said. 'specially if you've already told her and it's not getting through!

I've had to go all PA on my MIL when she's tried to undermine me. Took her a while to get it, but she plays by my rules now.

PA works well with my MIL :D 'oh no nanny forgot we can't go out today, we have plans, what a shame. It's ok to be sad darling you're disappointed now bless you'.
She's being PA by suggesting it to get her own way really, taste of her own medicine :)

Hmm, PA might be the way to go. It's seriously infuriating!
She does it with days out as well. We'll say we can't do so and so today, we'll do it another day.
So she'll say something like "aw, but then you're making them miss out." No, we're doing something today, and we said we'll do yours another day.
So no. They're hardly hard done by.