Uh, yes I am neurodivergent. (So are all my sons. Very common within my family.)
As are a lot of trans & nb people. Probably because they can't mask who they really are.
You don't say "hi, they/them" to someone's face, just when referring to them. I don't say "hi, he/him" to my kid either.
He's just him. Same as I know my step-gran wasn't my real gran, but called her that anyway.
The most common response when I told my friends about the boy's transition was: oh no, what if I mess that up? I reassured them he wouldn't mind accidental deadnaming etc, it's normal. But all of them met him, realised it was no big deal & just stopped worrying.
It's hard to explain, but when someone transitions (by which I mean drop the pretence of who they felt they had to be) it's a huge change. A whole new, totally authentic person is revealed to you. And you realise: this is who they always were. It feels right.
It's the opposite of pretence.
I felt humbled, because my god I wished I'd known earlier. He had been out to his friends for years before telling me. I felt like I'd only ever known a fraction of him.
It's not a case of 'lost a daughter, gained a son'. He is my child, and exactly the same person - except he now trusts me with knowing who he really is.
And being trans is the very least of that. He isn't permanently playing a character - just no longer living a lie. Even though he has had no treatment whatsoever, I see him as...himself. We talk about periods, street harassment, contraception, how to keep himself safe. I'm not buying into a pretence - just accepting reality.
Sorry, that's a lot! But there is nothing to fear from the truth, which is that trans and nb people exist.