Not allowed near my younger sister

I have a 13 year age gap from my younger sister, and the situation besides age is also complicated. First off, neither her bio dad or our mom has custody of her (we have different dad's). She was taken in by the grandma on her dad's side after both my mom and her dad lost custody when they were getting a divorce. Not going too in depth on that whole divorce right now since it doesn't pertain besides custody and such.

I identified as a lesbian for all my life before I came out, then 5 years before coming out as ftm I was nonbinary but the family was/is conservative religious and wouldn't know the difference between nonbinary and lesbian. It didn't matter too deeply as it was the same name and I really just changed my style, not my body.

Ever since I started T I knew it was going to change, because being trans is different than only being queer in the fact that my body is subject to change now. A little over a year ago I changed my name. I changed my pronouns to he/him and just about everything from a new inventive look with my hair, early on voice training, and my clothes. I felt vastly better, but I was no longer getting invited to family events with my sister.

My mom sees my sister on saturdays for visits as my sisters grandma thinks her mom should still be in her life, but according to my mom, unless I appear as feminine there is no possibility of me seeing my sister. Its a mindset of "this little kid has gone through so much already, the transition would be too confusing" as well as the well-known "she looks up to you and is impressionable". People really don't like to have difficult conversation with their kids. I mean they never even explained me liking women to my sister they just said nothing and whenever it was mentioned in passing my sister would laugh about it and be like "like a playdate? Girls cant date girls." Well, you know.

My mom is a distance person for a reason as well. She was a terrible alcoholic for years and still persists said old habits, and has always been a self-serving person probably due to such. She was trying to frame this situation as how she was so sad that her two *daughters* can't have a relationship. So as with everything, I make it so that she cant make it about her and I say that it doesn't really bother me.

A drunk tangent later after blaming my trans identity on this or that, we settle with the only thing I have; waiting until my sister grows up.

She's always looked up to me. When my mom had partial custody during the divorce she lived with me and my dad and we primarily cared for my sister. At the age of 19 I ALMOST took custody so she would be safe from foster care. I imagine she looks up to me so much after I was the one stability she had through a rough early childhood, unstable parents, and having to move house to house consistently.

She's being raised very conservatively religious so I can only hope that one day when she's older she'll want to reconnect. Really wish more people could just accept that they don't understand the transition personally but that they support. Its really just that easy, and explaining with "I feel" statements I believe coule really help any child understand something. The grandma doesn't want me in the picture, my mom has no say because she has no custody, so it is what it is.