AIBU to refuse a full early Christmas with young children?

Surely what they're suggesting is a bit like a communal birthday? I don't think your DC will be confused by exchanging and opening gifts and I'm always happy to eat a Christmas dinner! Putting up decorations early will be fun too. I would not do Santa Claus but that's my only hard line.

That’s very sensible.

Honestly, my instinctive reaction’s that there’s no way I’d arrange a second, earlier Christmas Day.
If little kids were not involved then of course it’d be grand, but as it stands I feel it’s a very great shame to dilute the day in this fashion, creating a duplicate.
If their brief years of wonder and excitement are worth cherishing and protecting, then showing them the ‘magic’ can happen at other times as well seems counterproductive. (I am taking it as read the OP always has a fairly trad Christmas Day, given the reason for the post)

All this ignores the actual story of Christmas of course.
Assuming any minority cultural tradition would have been mentioned, it’s a fair bet the children will know about the Bethlehem story (without any godliness attaching, to be sure!). Just the shepherds, manger, angels, donkey, and a tiny baby. Maybe the odd kingly wise man too!
This story can’t reasonably take place twice in one Winter, nor little Baby J have two birthdays, both celebrated with a day of gifts and festivities and special food.

Cannot the grandparents give the children mere tokens on their November visit, main presents hidden in the cupboard for Dec 25, and the family day be a wonderful celebration of Winter, maybe?
Decorate the house with greenery and holly, kids helping, light candles, drink hot Ribena/wine by the fire, watch The Snowman, etc, etc.

I am astonished at myself by the strength of my feelings here! I’d not have expected to want Christmas Day for little children to be well protected.
Put it down to advanced age.

You just call it granny and granddad's Christmas party, so long as no one says anything about father Christmas having been what's the problem? They get some gifts from grandparents and say thank you to the people who bought them, and eat a turkey roast. They will have christmas dinners at nursery/school etc it's no different

If they want to replicate Christmas, why don't they do it after they are back which is presumably sometime between Christmas and New Year? Also, if you don't spend every Christmas with them anyway, are you sure they mean doing full-on Santa, etc. Seems strange to insist on this if they might not even experience that on years when they are in the UK!

If agree to either your compromise before Xmas or their day after Xmas. Tell the kids father Christmas knew they were away and came back. But agree with you RE taking the shine off.

I don't get it really as we don't spend Christmas day with my family often and always have a second one if we don't. On top of that my kids alternate Christmases between me and there Dad's so there is no one day. I think the more Christmases you can get in the more fun it is.

I can’t see why you’d exchange gifts and not open them… of course they want to see the kids open their presents. I wouldn’t do a whole massive traditional Christmas meal though, too much effort twice over.

No, I wouldn’t be keen. Christmas Day is special because it’s Christmas Day, you can’t really replicate it. I’d veto a tree/presents/chocolates/carols etc! Just do a roast, theatre/panto and have a lovely November Sunday - if in-laws are so bothered about Christmas they should have booked their holiday for January! They can leave the presents behind for kids to open in December.

We do this every year. We haven’t seen three out of four of our adult children on Christmas Day for about 20 years. They all come to us a couple of days afterwards and we do a complete rerun with all the trimmings. None of the grandchildren are fazed by it, they love having two Christmases. Even if you don’t do the whole thing surely you’d open the presents you exchange?

Exactly what you are describing the in-laws want was a thing in my family for a bit. We stopped it as it was too much, and things are better for it. Don’t let it start!! The compromise day sounds great (and is sort of what we do these days to keep everyone feeling involved in Xmas).

Sounds pretty harmless to me.
We've done an early Christmas as DH's family often go away. We have Christmas dinner and exchange gifts for eachother.
The kids are told that we are celebrating with DH's family early as they are going on holiday. It's really not a big deal.

Are they envisaging Christmas tree? Leaving Santa’s food out? Stockings?

Be honest!

Your compromise sounds lovely.

It does seem to exclude PIL giving their presents. I'm not sure why. It's natural for them to want to see you all opening the presents and it won't be confusing for the children. Even if the grandparents say, "Happy Christmas," you can tell the children that it doesn't mean that it is Christmas ("It can't be Christmas yet, we didn't put anything out for Father Christmas last night and he hasn't been here and left your presents.") - it's just what people say when they give Christmas presents, even when they give them early.

As they’re the ones buggering off for actual Christmas and asking you to host, they really don’t get to call the shots, I’d have thought

Agree to replicate - but after Xmas would be my compromise

What is it that they want that isn't covered by your suggestion?
Decorating the tree, panto, a fancy roast with a nice pud, and exchanging and opening presents to & from the in-laws seems fine, and I'd happily accomodate that.

I'd not do Father Christmas until actual Christmas.

Are you one of those families where all the children’s presents come from Father Christmas, so in order for the grandparents to give their presents on Fake Christmas, you’ll have to pretend Father Christmas has come? That particular variation on the tradition has never really made sense to me, but it’s the only hiccup I can see here. Otherwise just do your plan, but let the grandparents give their gifts to your children as well, which I’m sure is the part they would miss the most.

ETA: Sorry, cross posted with OP! I’d let them do it, just without a big “waking on Christmas morning”
fandango.

I don’t think you’re being unreasonable. One it’s a big commitment to do two full Christmas Days and two I think it would take just a little of the shine off the real Christmas if you’d already done it all a month earlier! Part of what makes it special is the excitement leading up to the one single day.

Some people wouldn’t mind this at all and would crack on with two days, but I think if it’s important to you to preserve a bit of real Christmas Day magic and excitement, then you can’t do the whole thing in advance.

I would do your compromise but add in exchanging presents with them early, on their “fake Christmas”.

Tell the children FC only brings some some of the presents not all.

I wouldn’t be cooking Christmas food in Nov - the curry sounds fine - but if DH wants to cook a roast then surely he can!

Oh come on - all they want to do is go to the pantomime, have a roast and open some presents.

Anything more?

Tell your husband sure, go for it. He is free to arrange every single thing. Don't lift a finger.
He will also be answering the kids questions about why Santa has already been, how does that make sense, and their overwhelm at having two over hyped Christmases.