To expect parents in mid '70's to host Christmas with very young children?

I think you're being ever so slightly brutal here, OP. Your sister's a single mum with two small children. I really don't think you can assume that she's going to be inundated with offers from people who aren't related to her.

Everyone finds Christmas exhausting. Lots of parents in their seventies still do the hosting and enjoy it, the younger ones help them.

I've no doubt your sister helped out as well as seeing that her children didn't get over-excited at grandparents' house.

So your sister is single ‘by choice’. Good on her for getting out of a bad relationship. You seem you judge her for this?

I don’t understand what you’re really suggesting - are you saying everyone have Xmas at your parents’ but without your sister and her kids??? If so you are very mean and if I was her I would be really hurt by that. You sound very critical of her throughout your post tbh. You definitely should not do a family gathering and leave out one sibling and the children. Really you should host if it’s so much effort for your parents; your sister can’t. I suspect you think you’re a bit better than her so maybe you should be the hostess with the mostess! I don’t know if I’ve understood what you’re saying. If she has just invited herself to theirs and you aren’t going then really it’s up to them and not your business to be involved in.

To be fair they paid for the turkey which was the expensive part of course. Initially she would put the turkey in and I would bring the rest and finish off when I got there, but in the end it was just easier to do it all at my house and take it over - otherwise she was fretting about whether it was cooked and when to put it in. But all this because she (and it was Mum really) couldn't say no, and my sibling couldn't be told no. When she went there once, she ended up cooking anyway, in a strange kitchen (sibling helped tbf).

How awful. Your poor sister...

70s isn’t very old, my 70 old MIL has much more energy than me and loves to host Christmas. Although we haven’t been in years. Christmas doesn’t have to be that stressful, it’s just a roast dinner really!

Ultimately, it’s their decision, if they are fine with it then it’s not really your business. It also sounds like you really dislike her. You don’t have to invite her to your house but to actively stop her from getting another invite is very mean.

Exactly, 70s isn't old these days, my MIL is going backpacking solo around the world.

I think mid 70s most people would be perfectly able to make up their own mid. It is also a age range where there is a huge range of what people expect to do - some have been retired 20 years and completely slowed into pensioner life other will still be spring chicken like.

Do you think we’re unreasonable in regarding mid ‘70’s as too old for hosting Xmas for several days with very young children?

YABVU. My DH is early 70s and still MD of a growing company (which he founded) and renovating a French wreck on weekends/whenever he can sneak a day off. He'd be pretty horrified if I suggested he was too old to host his grandkids for a few days over Christmas.
Not your decision to make OP.

Don't interfere. I think it's very cruel to suggest that your sister should be without her family at Christmas when she is a single parent. Your parents clearly want her there even if it means it's tiring for them.

Would you turn one of your children away at Christmas when they're older?

It sounds like your parents have plenty of money, could they not go out for dinner with your sister and her children to cut some of the stress out?

I voted YANBU as you're trying to ease the burden on your parents and have observed that hosting is tiring for them, but I'm wondering if the wording of the thread title is the reason for some of the YABUs on here as it can be read as though you're expecting your parents to host.

You don't seem bothered that neither you not your grandchildren will see your parents at Christmas, so it seems a bit harsh to choose to abandon them and then say your sister and other grandchild/ren also can't spend time with them. As you say, they are mid 70s. Not many Christmases left.

It's for them all to decide and literally nothing to do with you, you've chosen to remove yourself from the equation.

Where did your sister & child/children go the last two years when DP’s were at yours & DB’s?
It’s unfair to expect her never to share Xmas with her DP’s. She can’t host, so it has to be at theirs. Perhaps speak to her/DP’s about ways she can help & make life easier for DP’s.
Alternatively, book a big self catering property somewhere central for more of you, so more adults to help with food & you or your DB can ensure DSis pulls her weight.
Regardless of any back story (excluding abuse) it’s seems callous to leave Dsis out every year.

This. It happy tiredness becuase you have spent time with loved ones, surely

Nothing bonds people like a common enemy. The Black Sheep Sister has neatly provided this for OP and brother (and possibly even Dad). So they have a lovely, slimy subject to agree about while making themselves feel moral and charitable.

The problem with this is that if the common enemy exits or becomes less problematic, the group casts around for a new one. Could be OP if she doesn't watch it.

I think even if your sister is a right royal pain in the arse (and OP, I have one of those so I sympathise) you have to put up with her over Christmas, for her kids' sake if nothing else. They deserve to be part of a loving extended family and it's really unfair on them if they're punished because their mum is hard work.

I agree with not liking the "inviting herself" comment. I would be bloody heartbroken if I couldn't go and stay with either of my parents, particularly at Christmas. Most people's parents make their kids feel welcome at ALL times.

But just because you're all going there doesn't mean your parents have to do everything. You should all work it out between you so that you do all the work and your parents can relax.

Accommodate your in-laws but not your own sister? Riiiight. Do you even realise parents take these things into account when considering their end of life decisions without mentioning their decisions to their children they have observed being horrible to their siblings? You have time to rectify the situation

Life would be boring if we were all the same. So what if she is a different family make up to her amazing brother and sister.

At the end of the day they are all adults. They have said yes and the child is a year older and maybe a little easier to handle. You have no right to interfere imo.

What you could do is broach the topic with your sister about how tiring it might be for your parents and to suggest/ask your sister to try to make it as easy as possible for them.

Otherwise, stay out of it.

So basically you are saying that your sister should not spend Christmas with family, is that it? I mean, you are not saying it explicitly but all other options are impossible according to you.

If your parents are saying yes to hosting her why would you think it is your place to tell her she shouldn’t go?

The "baby" is now another year older and presumably less likely to be fractious in the way they were at 5 mths which to be fair is what babies do. Frankly I think you are being a bit snobby about it all and seem to have an issue with your sister going to see Mum and Dad cos she has younger children and its not so easy for them these days - whilst your Mum might have been shattered she probably wouldn't have it any other way as she also wants a relationship with your sisters children and sees that your sister is on her own family wise and despite a good friendship group may well be left alone at home for Christmas if she didn't visit family in the same way 95% of the country do.

A Lot depends on how lively your parents are etc but for a short 5 days visit I would keep my nose out and let your still compus mentis parents handle their own lives without you and your brother running unwanted interference.

Just because your sister has a good social group it doesn't mean she will be invited with two kids elsewhere. People are madly busy at Christmas with family, extended family, In laws and don't necessarily have the interest or space in bringing others into their Christmas plans. I'm sure anyway your sister would prefer her own parents anyway. If you don't want/can't have your sister yourself I don't think you should be resentful about her spending time with your parents. Maybe you resent her having a more relaxed Christmas break there than you are going to get doing Christmas at home ...or maybe You resent that having your sister means your parents can't come to you. In any event why consider interfering with other people's Christmas plans? My DH and I are 72. We do Christmas every year still.Ww make it lovely and yes we are exhausted afterwards ...but we wouldn't have it any other way. Loads of people of all ages host Christmas then have a bit of a moan later about the expense and exhaustion ...but still do it all over again next year. Because the family gathering ...maybe only once a year ..is important to them. It would be a very lonely Christmas for your sister alone with 2 small children. If you can't ...or don't want to host her ...leave hers and your parents plans to them.