Advice

My sister came out as trans last year ( MTF) and it was pretty hard for her. Well, since she started talking to me about it I’m starting to think I’m trans (FTM) and I want to come out too. She supports it 1000% but I’m afraid my family won’t take me serious. My sister is 24 and I’m 16. I think they’ll say I’m too young to know. But me and my sister always knew we wasn’t in the right body. Even when we was kids. She use to call me her little brother and it always felt right. What should i do?