My family always get together for Christmas at my GPs. It's been that way since shortly before the signing of the Magna Carta. And she lives a six hour drive away, so it inevitably involves an overnight stay.
I've been married to DH since 2007, and he has two DCs from a previous relationship. For the first two Christmases since we got married, DH and I organised with his (local)XW and her new DP for us all to spend Christams with the DSCs together. It has been mostly remarkably amicable.
However, DH and I had our own DCs (twins) in February, and my mum and dad are now putting pressure on DH and I to spend Christmas with the rest of my family at the GPs. Which is fair enough, except that my parents and GPs are stipulating that we must bring only the DCs and leave the DSCs with XW. They don't have space for four children, and they don't approve of the DSCs and their table manners anyway.
Certainly, we could muddle together some sort of diplomatic arrangement to ensure that both my family and the DSCs get equal time with the DCs, and I'm sure both the DCs and my parents would be grown-up about it. But given how hard the DSC's family has worked to be welcoming and accommodating to the DCs (XW has come round with meals when I've been too tired to cook, and has babysat a few times when the CM was ill), the unwelcomingness of my family seems very harsh.
But AIBU to think that, as a general social principle, you cannot invite a person's DCs without inviting their DSCs?