Why are they trying so hard to prove it, if it’s the obvious truth? I never saw my mother and sister having to prove or defend the point that they are women.
Well, regardless of my standpoint, I might not like what you have to say but I will for sure fight for your right to say it. Same goes for everyone.
If you spent more than five minutes looking into this you'd understand that there's a whole lot more to it than presentation. Some people are born intersex. Some biological women are born with two xx chromosomes. Some biological men are born with xy chromosomes. Etc etc. It's nice that your mom and sister have it all clear. A good portion of humanity has to fight to explain their place every day