my parents didnt want me to know that my older sister was trans but she told me anyways, and i've heard what my dad's like with the talks he has with my sister and how he doesn't like that she did that, but there wasn't any reason she couldn't tell me. you shouldn't think that because she says don't tell anyone, doesnt mean you have to listen because something like this isn't her choice, and you didnt have a choice to be happy in a body you're not. you have the chonce to be someone you want to be, and the choice you do have is to be open and happy with people you know after telling them you're trans; if you want to/when you're ready of course. my parents have been the same and you're not the only one going through this and i'm right here for you if you ever need someone. i'll do my best to be on wattpad if you'd want to talk but i have screentime unfortunately. the way my parents are with my sister being trans is the same reason why i havent told them i'm trans, too, but i just prefer saying demiboy at the moment. i've told them i'm bi, while feeling forced cos i was stressed and my mind was everywhere all at once, but i'm definitely not ready to tell them i'm demiboy, and they're not ready for that either. try to think of all the other people who support you and are here for you, and the chonce that you're mom might come around and feel comfortable about it and more supportive