To Tell SIL To Stop Claiming Things?

Just act as if she hasn't said anything. No looking her way, no uncomfortable "no". If she tries to monitor who wants what to eat just tell people to fill their boots. Let all her comments fail to land. If she tries to claim things at the end just tell her that that's not happening any more.

I was going to say similar. A single word or short phrase on repeat: 'No' or 'Stop it' or 'Rude'.

or literally play deaf. Don't acknowledge, not even with a nod or eye contact. But ensure anything she wants you to save her for later gets handed around the table until it is all gone. If she whines I'd go as far as saying 'Shut up'. Rude people should be able to cope with rude responses.

wow. It’s is not BIL responsibility to manage her behaviour. She’s not his pet. OP needs to talk to her directly.

My Step mums sister was like this. I once watched with an open mouth as she picked up the present I'd literally just given my dad and walked off with it to her room! no asking just taking.

I told my dad and he rolled his eyes and said he'd get it back.

I also found the CF rooting through my cupboards when she was brought over for a visit once. She was never invited again.

I challenged my Step mum on the behaviour years later and she said 'well maybe she was just curious'. I said 'does that mean I can root through her stuff then?!'.

Interestingly it didn't seem to work both ways and she seemed quite aghast at the suggestion.

Odd family to be honest that I'm slowly fading out after 30 odd years of putting up with.

This! Be terribly blunt when she does it. If she tells other guests to stop eating - “SIL, please STOP doing that. Everyone is welcome to eat as much as they like. Besides the leftovers are for me to enjoy seeing as I cooked it!”

“Stop asking for my presents you weirdo! Are you going to give me some of yours?”

if she does anything a third time, say to them they will have to go home as their behaviour is spoiling the day.

I would turn it around and comment to BIL . When she asks for a gift "oh BIL maybe you can treat you wife to the same " when she asks for left overs " oh BIL you need to start buying more food your wife is going hungry at home "
Turn everything to BIL make him embarrassed.

She’d rather not be invited if she’s not interested. There you go. But I will caveat that with it sounds like it could be a compulsion. OCD can take many forms.

So you could text…

Dear SIL. We are looking forward to seeing you and BIL at Xmas. )some chit chat here(

I need to make an awkward request. I know you love getting something for nothing and it’s really important to you. The trouble is that I find it really uncomfortable when you ask for our presents if we don’t want them or ask for left overs. It means that I don’t enjoy Christmas as much.

I understand it might be a hard habit to break but I would really appreciate you trying not to ask for things. Also, you once said about X’s dinner that you don’t want to pay for something you are not interested in and you’d rather not be invited. If this is one of those events you are not interested in then please don’t feel you have to come.

I’m going to set a new household rule. Nobody takes any leftovers home and our gifts are not going to be passed on. I hope this helps you to relax rather than looking out for what freebies you might get. Looking forward to spending time with you both.

OP I’m not sure if that helps but if you do send something similar be aware it might cause a rift. Check with DH first as it’s his brother. If you do send it you can say ‘remember the house rules’ and smile and have some things in mind to move the conversation on.

100% needs addressing in advance, with last years behaviour as evidence - "Barbara, I thought I'd call and let you know in advance that we have plans for the dinner leftovers this year - I remember last year you kept asking to take leftovers home so I'm telling you while you have chance to go to the shops to get your own bits in. While we're chatting, it made me uncomfortable last year when you kept asking for my gifts, please don't do that again.
Then on the day, if she does, you can just say "Barbara, we talked about this, no"

Many of these suggestions will make other guests feel awkward. I would go with being quite breezy and laughing it all off getting firmer if needed in private as the day goes on. No way would I give her any leftover or extra gifts. I'd also tell your husband to tell his brother that if he doesn't want his wife to feel embarrassed he better tell her not to behave this way because you will be calling her out. This warning might help tone her actions down.

I don't think thus should keep you awake at night. If she asks to take stuff home just say "Sorry, we were planning to eat that ourselves." It shouldn't be so awkward.

I once heard a friends DC reply to this..... they said

'the n part'

SIL has no shame at all, it's BIL who gets embarrassed and wants you to indulge her. Tell BIL before they come that SIL's scrounging embarrasses everyone and it is not going to spoil everyone's xmas this year. Remind them on arrival that Sally is not to scrounge today. Tell other guests as they arrive that you are not tolerating any scrounging by Sally today. Then every time she tries anything just say "stop scrounging"

I'm assuming that it is the same group of relatives/family friends every year. If there are going to be new people in the mix, just prewarn them that SIL unfortunately will scrounge given any opportunity and just ignore it.

It's worth one Xmas of BIL being embarrassed. He either then has to do something about her behaviour or they don't come again. She was very open and rude about the dinner so you should reflect that attitude back at her.

I’d go all faux concern, take her to one side and say ‘I’m really worried that you keep asking for things, is everything ok at home, do you have money troubles?’ And when she says no then say well it’s really weird so stop it,

Crikey I would reprimand my children for doing that.
Time for some good old mumsnet stock phrases
No it's my gift, why are you being so rude
No sil we are using leftovers for boxing day
Sil (tinkerly laugh) don't be silly people cn eat much as they like, WE paid for it
Sil do you mean to be so rude (headtilt)

That’s your opening, if she has said in the past she’d rather not be invited than pay her share just use her own words against her if she moans.

I don’t think I’d uninvite them simply because we’ll, it’s Christmas, but she needs calling out.

Quick text to SIL in advance:

”To avoid any awkwardness on the day, I will be keeping all of my Christmas presents this year, and won’t be providing leftovers to take home. Please don’t ask”

This is what I was going to say.

Reply NO every single time. Let the other guests know to do the same. Emphatic NO.

Does this grabby woman bring any sort of contribution or gifts for the host?

I’d shut her down by acting like everything she says is ridiculous, so…

can I have this present? No, of course not it’s a brand new gift.
If she asks again - Bloody hell, you’re like the grinch, no again, you can’t take brand new presents!

Everyone, don’t eat all the carrots, I’d like to take them home - haha, don’t be daft, everyone tuck in!

I suspect that it’s actually your BIL who gets embarrassed, hence why he doesn’t want you to say anything.

I know this is a joke - but my autistic DS hates when his food touches and this plate would save me so much hassle. (He hates the plate dividers too 🫠) so thanks for sharing!

OP, this needs to be nipped in the bud. Is she frugal and saving or very very tight and forcing herself without? Either way, very unhealthy and not the sort of dinamic you want over Christmas.

Surely not too late to cancel, there’s still time to go food shopping. And when they do, maybe SIL can ponder why they’re there doing it. Actions, consequences, all that. (And totally agree re female life cycle!)

I can't believe she refuses to pay her share of a family meal, so making it more expensive for everyone else presumably, who then have to pay her share!

If she doesn't care about offending you and others, then I wouldn't worry about uninviting her from Christmas dinner. Do it, it will be empowering. She's brought this on herself, she's relying on everyone else's politeness to get away with it.

I would speak to her today. Tell her she is welcome if there are no further comments. No asking for leftovers or wanting other people's presents. Tell her it's embarrassing and upsetting.
Suggest that if she can't keep her trap shut for 1 day then she needs to stay at home. You will probably be more polite than that!
I really would not tolerate that, it's utterly lacking in manners.
Edited to add. Shops are open so she can still get stuff in for Christmas dinner.

So to me my two options are ring her in the morning and tell her to not behave that way or uninvite them both and tell BIL why. I simply cannot have another Christmas day like last years.

I don’t think those are your only two options. I’d have Christmas as planned, assume the best and if she starts, make a point of it and laugh it off.

The food thing is bad enough but presents? What scale of present are we talking about? Jewellery from your DH, chocolates from an uncle or just everything?

Eeerrrrr that's offensive to people with Tourette's syndrome !!!!!