My formerly estranged brother has transitioned and wants back in mine and my mother’s lives.

We have a newly transed niece, complete with a shiny new name and pronouns.

Given her other issues the fact that she has now proclaimed herself a “man” was fairly predictable.

The entire family thinks it’s offensive nonsense, but we are all keeping our mouths shut, for the benefit of the girl’s mother.

So no one has said what they think, or in fact addressed it at all. We politely use the new name if we can’t avoid it and have so far successfully avoided using male pronouns.

The unfortunate side effect is that no one directs much conversation to the young woman concerned or asks much about her anymore for fear of accidentally setting off a familial nuclear bomb.

If your brother isn’t a nice person, I would advise quietly supporting your Mum and otherwise saying as little as possible and staying well away.

I think I would start by supporting your mum. You can do that by talking to and listening to her.

I don’t think you need to be proactive, on contact with you the ball is in their court. You’d expect in any circumstances some admission of past failings or failing that some acknowledgment of wanting a fresh start. If you don’t get either of those things then I wouldn’t hold out hope they’ve changed.

Any reconciliation is always a slow process with work on each side. And often stop-start. I don’t think you need to set out your position on trans stuff, it’s too early.

I think you should go with detached indifference. Don’t discuss anything with him, don’t use his new name, just say the least amount possible and be ‘busy’ if he asks you to do something.

@AralVorkosigan has it bang on

I personally would move heaven and earth to make sure he was kept well away from my kids. They do not need this from someone they do not even know.

He’s contacted you to say he wants to be close? Or your mum has told you that?

Oh and if your mum or he push for a nice family Christmas, I'd have already made plans. It's a stressful enough time as it is and you'd have a job keeping the kids away from that one.

If he's not spoken to you about it I think the discussion is a moot point given you only know from your Mum and she wants to see him.

You've managed for years without him and presumably as your DC are young he's never been in their lives.

He has deliberately 'forgotten' his past behaviour and probably wants contact now so that you can pander to his bravery and lovely womanliness and validate his delusion. You don't want him back in your life so trust your instinct and tell your mother you appreciate her not wanting to be cut off (the very epitome of trans gaslighting btw) but that you will not perpetuate his fantasy, nor do you want your DC to be brought into this world of batshit, and therefore will remain NC.

I don't see that you need any conversation with your brother. Your Mum wants a relationship with her son, and is willing to tolerate his beliefs, in order to maintain a relationship. It doesn't mean you have to do the same.

You don't want a relationship with your brother, you just need to be able to tolerate him at family gatherings. That means being polite and civil. If being civil means referring to him by his new name, then is that any real hardship?! It's a name, nothing more and doesn't mean you agree or support his decision.

How old are your children? Old enough to know and remember you have a brother? With most young children, if you introduced your brother as 'Mary', then they're likely to just take the name and him at face value. If they're a lot older, then yes, you may need to explain your brother is trans, and what that means.

Your father’s death may have hit him hard and he genuinely want to get close with you all. He may of struggled most of his life with feeling he was born the wrong gender and want you to get to know who he really is and make amends.
You don’t sound like you would accept him as he is though and that will create a lot of angst for your mum. You've also made it clear he has been awful in the past and that you can’t forgive him.
I would stay away @Rimding

Hopefully friendly just means civil if you are in the same room. He can't expect an actual friendly relationship given his previous behaviour.

Tell your mum you don't want to talk about him, and change the subject.

Don't reply to any contact directly from him - blank him or even block him.

If your mum sets up a situation whereby you walk into the room and he is there, you have the choice of walking straight back out again, or staying in the room but essentially blanking him or being formally polite and distant (may depend on how many people are in the room).

Ultimately, your mother has to accept your right to see who you choose, and cannot force you to have a relationship with him. If it comes to it, you may have to tell her that if she keeps pushing the issue you will see a lot less of her.

@Rimding if he gets in touch and you’re ambivalent/keep your boundaries and he asks why, just keep it to the truth - he wasn’t nice to others/nice to be around and not a good role model for your kids. The trans bit is kind of irrelevant here and his prior behaviour is enough to make you cautious. I’d say nothing for now but watch and observe.

If he wants to re- build a relationship with you, maybe leave your children out of it for now and see how it goes.

Then have a think about how you want to relate to him. For example
Will you not attend a family gathering if he is present?
Will you attend but be aloof but polite?
Or will you be friendly but not accept any contact over meeting at a family gathering?

Figure out your lines in the sand now before you're caught like a rabbit in the headlights when something is suggested or sprung on you

Base your thoughts on the person he is/was. His gender related beliefs aren't relevant other than the confusion he presents to your children. But he won't be the only trans identifying person they will come across and you have most the influence on how they interpret what they see in the world when they are young enough to still think you know everything

Just protect yourself. Your mums relationship with your brother is their own, doesn't have to be yours.
Estrangement normally has a valid reason behind it and I presume that wasn't taken lightly at the time, so no, I'd not be in a hurry to introduce him to your children or back into your lives. His wants do not trump your own.

I suspect what he wants is validation, not involvement. All The Girls in his family supporting his notion that he is one of them.

He wants support animals, not an equal relationship with real people.

Yes, to be fair his late onset transness is a red herring here. The estrangement is because he is clearly horrible. And I can't imagine he has become any nicer, just more entitled. He can want what he wants, you don't have to cede to it if you don't want to. I can see why your mother might want to, and that's her choice, but she doesn't get to make it for you too.

That is your prerogative as their mum and it’s not unreasonable to not want a relationship with him again because of how he has treated you in the past.