I only had this situation with one of my d.i.ls but my son made sure he came round regularly. Now they are divorced and things are much better as the lady he is now with is entirely different. My other 3 sons and my daughter are very close and ring or visit regularly. I also have a great relationship with most of my grandchildren, particularly the eldest one who used me as a sounding board when he was thinking of giving up his job on the oil rigs and going to university. He got his degree and is now living in Japan but still keeps in regular touch through viber.
The suggestion that the OP should do a buffet is not very practical unless she was to have an idea of how many people were going to turn up. Everyone I know does far too much food for a buffet, even when they know how many are likely to attend.
My solution for future Christmases would be to arrange to go away, either in the UK or abroad. I would love to go away and would do so if I ever felt my children were stressing about who had to have me, but it seems things haven't got to that stage yet.
Which British song sums up the 1960s for you?
Times article claim that Waspi women are tone deaf and should read the room


), I would suggest to your DD that the next time her inlaws cause a problem by visiting at a bad time, that she comes over to you as arranged (with or without the DGC), and leaves her DH to look after the inlaws. If he is out, tell her to come over to you on her own and leave the DCG in their care. Alternatively, she needs to agree a new time with her DH for her to meet up with you and him to look after the DGC. Maybe then he'll start tackling the problem. 
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