To cut my sister off for this?

As you don’t have much of a relationship, cutting her off won’t really change much. It just means you won’t reach out to her, as it sounds like she doesn’t reach out to you anyway.

But it also sounds like you do want a relationship with her or you would just put her out of your mind. What has she said to family members - does she also wish things were different? If you both do then there’s still time to improve things, although you may have to do much of the work. But if she’s not bothered, it’s better to let sleeping dogs die and not try to force it, or you’ll end up feeling worse about the situation

Look your coming across as a demanding bully whos creating drama out of nothing because you just dont like her.
i could very well be wrong here but I'm going to guess that you were an only child until your sister came alone and at age 5 suddenly not being the centre of attention anymore really put your nose out of joint and you've never truly got over it and you still blame your "annoying" little sister for everything. Hence your creating another family rift and trying to make family members pick sides again, 1st you don't speak to her for 10 years because of a rumour which she denied yet you chose to believe because she couldn't possibly be telling the truth right. Then you suddenly decide to forgive her out of the blue for your imagined crime, only to create more drama because she didn't show what you deem to be a suitable level of concern for you, and now you're using your youngest sister as a flying monkey whilst running round the wide family slagging her off.
Ofcourse she's justifiably angry with you. When are you going to get over yourself and give your poor sister and wider family a break from your endless drama

I agree with this.

I’m sorry but you seem like hard work yourself.

Why on earth do you feel the need to “cut her off” - such needless drama. Just leave her be and be nice when you meet at family gatherings. You sound furiously needy and determined to make a huge thing of this 🤷🏻‍♀️

It seems as though it's absolutely fine for you to slag her off behind her back to anyone who'll listen, but woe betide she do the same to you.

Try to see it from her perspective. For most of her life - maybe back to her earliest memories - you've been the big sister who doesn't like her. Maybe she's never had any clear sense of why. Perhaps to you she was "annoying", but perfectly ordinary children are annoying to those a bit older than them. No wonder she's on eggshells about whether she should be in touch with you.

I also wonder how the event ten years ago fits in. Which of you was more at fault, would you say? (You don't have to answer, but it's worth thinking about.) Is it possible from her perspective that this was another case of nasty big sister kicking up a fuss over nothing?

So just leave it. No drama. No falling out. You don't have to be close with every family member.

Say Hi and be polite when you see each other. You could even do cards at Christmas or birthdays or just a text. Or nothing at all

Life is too short. No one needs the hassle. You do you.

It’s not clear to me — do you like this sister? Do you love her? Everything you say suggests not, but you seem to be very preoccupied with the kind of relationship you think ‘should’ exist between you.

Nothing in what you’ve said suggests she’s ’cold as ice’. You just don’t get along with one another, which is fine. You both have lots of other family that you do have good relationships with. You don’t need to ‘tell your children’ anything. My DS has an uncle he’s never met because he’s estranged from most of the family. He just accepts that.

But you're not happy are you? You're starting threads about her.

Seems like you want it all your way.

You honestly just sound fundamentally incompatible.

My sister and I are like this. We just can't seem to escape misunderstandings and actions being seen as hurtful even when that wasn't the intention.

I am someone who won't ask people about sensitive things, I feel they will come to me and offer up the information if they feel comfortable.

Many people appreciate this, and people like my sister don't.

I care deeply and show it in other ways, but to her the differences in our communications styles are insurmountable.

Neither of us are wrong, we are just two people that would never choose to associate or be friends if we weren't sisters.

Sometimes its not enough to be family with someone and it is okay to realise you just don't enjoy each other.

How old are you both OP?

It feels like you are looking for a reason to cut her off. In all honesty have you mentally really buried the hatchet? You sound still very much sore about the past.

Stop seeking some imaginary ‘perfect sister’ relationship and just foster, accept and enjoy the one you have. You don’t have to be in each other’s back pockets but family will often be there for you when others who message you with cringey ‘how are you hun’ messages are long gone.

Your children will be free to build a relationship with her or with her children in future. You can continue to invite her to family events if you want them to maintain a relationship growing up. That doesn't mean you need to have a relationship with her.
Nor turn it into a pile of resentments to bring out in future - some people just are who they are and let it be.

Be aware that often people can agree with you because they are afraid of disagreeing with you or questioning your approach OP . That creates an echo chamber of your own thoughts and actions where you believe only your perspective is right. We all need people in our lives who constructively question and challenge us. As the saying goes the common denominator in every situation we are in is always ourselves.

yes I used to think she was annoying as a child but everyone else in our family thought the same

I used to think she was annoying but so did everyone else

I'm not sure that she is the problem here and I wouldn't be too confident 'everyone else' wasn't just saying what you clearly wanted them to say. If everyone else has a relationship with your sister but you, why do you think that is?

I think it's unusual to talk to multiple siblings and cousins each day. If you are basing her lack of communication on this standard then you will be disappointed. I also think maybe she wants different boundaries. I wouldn't cut her off, I'd develop an adult relationship with her, which is about respect and acceptance.

It's pretty simple, OP. You want her to be someone she is not. You can't accept the person she is and hold her in contempt for it. You ascribe motives to her behavior that others tell you is not there, and from the description you have given I would agree with them.

She clearly cares, but from a respectful distant. You see this as uncaring and are angry about it. You want a big demonstration of how much someone cares about you difficult times and that's just not who she is.

If you don't want to talk to her anymore, that is your busness, but do everyone in the family a favour and stop turning this into a grand, dramatic performance. Just make your choices and live by them, without expecting your family members to be your cheerleaders or to even agree with you.

You sound incredibly dramatic.

You were never close as children, have barely spoken for a decade and yet now something has happened, you want her to forget all that and come running to your side?

As for what you'd tell your children if she has children and they're not close - I mean, really?! Why would you need to tell them anything?

From what you've written, she's distanced herself because of your behaviour and CBA with your drama. Unless there's particularly dreadful behaviour from someone, 'cutting them off" is unnecessary, most people just steer clear, are civil when needed and let matters lie. The fact you've already tried to get the whole family on side suggests that's not a very you approach.

Some people just can’t deal with other people’s feelings. You had already had years of estrangement and perhaps she genuinely didn’t know what was the best way to approach this with you - once you brought in your other sister, she knew she was always going to cop it no matter what she did or said, so she chose to stay out of it. The fact that you are here asking it is clear you haven’t let it go.

I am with your sister here. If I had a tentative relationship with a sibling who had something happen to them, then it makes sense to be cautious about approaching them and find out from others

Then you being pissed off about that and thinking I was a gossip would piss me off when I knew that I was stepping back for a good reason

Either accept that you will never have a relationship with each other, thrash it out between yourselves or go for some counselling to get to the bottom of this animosity

I think you are taking her actions the wrong because of the past.

She asked about you and didn't want to plough in when as you say you aren't close and it's all tentative.

Why can't you get in touch and explain you would have felt touched if she'd dropped you messages etc. Then ask her what would she like you to do if she's ever unwell/in crises.

You can't assume everyone thinks and feels like you. Other people would have felt it very intrusive of her.