I read your post and felt anxious. You are anxious. You are taking on a lot with a fragile DIL, mmmm.
But at least if the place is a disaster YOU didn't book it, so that is one for the bright side.
You can't make everyone happy. You can try, but in the process you can make yourself unhappy. Dirt is 'not end of the world' stuff.
So I think you should try and relax and keep away from the kitchen, take your own rubber gloves, Dettol Mould and Mildew remover, scourer and just clean up as necessary to make you happy.
You obviously cannot rush in and fall to the floor mopping, as your sensitive DIL will see it as critism of her choice. I wouldn't even mention your fears to your son. He is bound to go back and say to his wife ' my Mother said' That will be the end of you and next year no Christmas invitation will be forthcoming.
Be philosophical...what do you want? To see your Grandchildren with dirt? Or see no one and you sit alone in a pristine place?
Reducing contact because my heart just isn't in it.
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