MIL was round today to drop presents over for the kids, we did a little buffet and had a drink etc.
Then SIL turns up with presents (even though we are seeing them on the 27th anyway to exchange/open presents with their kids and ours etc anyway)
"Oh is mum here we didn't realise!"
So DH invites them in and they say yes.
Turns out they DID KNOW MIL was here, and MIL and them had planned it so they could all spend time together at our house.
Our house is small, and we didn't want a big event, especially seeing as we're seeing them anyway just after Xmas.
AIBU?