To not invite sister to social gathering

It's presumably not a military operation. I imagine it's quite informal, it's meant to be a nice social occasion. It wouldn't bother me at all if someone invited their sister. But you're right, lots of people are very uptight.

”This is MN” - we’re still trotting out that hoary old cliche, are we?

I’ve enjoyed meeting friend’s siblings before; one has become a good friend in her own right. What I would not have enjoyed is having a friend’s sibling sprung on me at an event where the rest of us had agreed we weren’t bringing guests.

My first thought was “let her come “, but I’d be a bit annoyed if we had a group event and the leader brought her non member family with her because it’s a group event. Plus if your sister has not felt able or willing to join the group why would she want to come and what would she have in common with everyone else? So no.

If the sister is struggling to meet friends… she can join the group!!

its totally not cool OP to have your random family members there if they are not in the group. I’d be pissed off unless she’s made some attempt to attend sessions beforehand.

if sister is too shy or lazy or whatever to join the group, she’s too shy to impose herself on a group for their fun social

I think its bad form for a leader / leaders family to invite someone to a social, if no one else has been told they can invite a +1. Its a hobby social not a general social. I think you will have to say to everyone else that if they have someone that might be interested in joining the group, they are welcome to ask them along to the social. Or say to your sister that she can't come. Otherwise it looks like one rule for your mum and another rule for everyone else.

Plus from your sisters point of view I'd think it was easier to join in with the hobby (where there is a defined end time and a purpose to the meet up) rather than a more unstructured social with people talking about more random things

I think it would be great if she actually came to the activity - to which she has been invited

But the 'do' has been arranged and it isn't for +1s whoever they are.

So because the OP's mother has overstepped, the OP has to change the plans which presumably the rest of the group had agreed to?

You think that's ok?

I actually am a bit surprised at these responses, in my mind it wouldn’t be ‘fair’ to invite your sister as she isn’t a group member when it’s not an option for other group members to bring ‘extras’ who aren’t in the group. It could create bad feeling within what is a nice group for you.

You're right. I was thinking how I'd like to meet her if I was in the group. How it wouldn't bother me if the leader's mum invited her daughter. But this is MN. My mistake.

Why would they?

That's not the point of the social - it's for people who already know each other

There could easily be 'open' events next year to encourage others to come along

Trouble is @NoSourDough there could well be family fallout if you disinvite

Have you had words with your mother?

It's a community group, not a cult. Invite your sister

Exactly this

It's bizarre that there are still people posting who don't understand that at a members only event, where plus-ones aren't invited, the leader bringing her sister along is simply wrong.

It doesn't matter how nice it would be for this shy sister. In fact it would actually make the experience more difficult for her, because the rest of the group would be looking at her and muttering about the unfairness.

When is the event? Is there time for her to join up (apologies If I missed it), then if she refuses to join she doesn’t get to go to the dinner?

if it was something informal like drinks at the local pub then yes she could come, on the basis that any other group members can also bring friends/family

but you've said it is something with a specific number of places (e.g. table booked in small restaurant), then no, it's not fair, and I can imagine the other people would be a bit annoyed, even more so as you're the group leader, your mum already comes and now your sister, who none of them know is rocking up as well - they might start thinking 'is this a hobby group or OP's family reunion.'

If your sister is too shy to come along to a group meeting when both her sister and mum will be there why would she even want to come to a night out? Usually the meeting would be a better way to meet people because there is structure and something to talk about, just meeting and chatting at a restaurant or pub would be more intimidating, I would think.

Could you go to the restaurant just the group and then say 'we'll prob go to the pub after, sister (and anyone else's plus 1's) are welcome to meet us there?'

I can't understand some of these earlier replies

It's a group activity so why would your mum think it's ok to invite someone not in the group

If your sister wants you to chi one , she joins the group

I'd be pissed off. She's not a random to you, but she is to everyone else in the group

Actually it's really high handed of your mum to be so presumptuous

It's tricky, what if everyone else in the group turns up with one extra person? You wouldn't be able to refuse for fear of being accused of nepotism. Does your Mum expect this special treatment at all her social groups or just the ones you run?

This isn't that different to dumping all your kids on someone hosting a bday party which is always frowned upon on MN.

I think the only way she should come is if she joins the group or you tell people that she is joining in the next term

I'm thinking if your sister has been too shy to go to the group (where there would be a focus/distraction of the actual activity) it would be surprising if she felt comfortable going to a social event where she doesn't know most people and where the activity itself won't feature.

Maybe if she does come it will give her an intro into the group though.

I can see what you mean about members only. It feels like you have organised a members only event but changed the dynamic only for a member of your family. You could open it up by saying +1s are welcome but again it's a big dynamic shift from what people have signed up for. I think I'd be mildly annoyed with my mum too because she's put you in that position. Chances are the group won't mind at all but you might have the niggling feeling that they might just think you/ your mum are being a bit CF.

Back to original point ... she probably won't come!

If sister wanted to meet this group wouldn't she have done so by now?

Your mum could arrange her own thing & take your sister!

There might be men at the social/group anyway, that's irrelevant

I don't think you're being unreasonable. If other group members aren't able to bring partners/siblings/parents/children (adult or otherwise), then why would your sister be there?