Yes, I have this too but it doesn't bother me.
I often get mistaken for a highschool student and people have asked if my parents were home when I answered the door at my own apartment
. I think it has something to do with how I dress and carry myself. I still tend to think of myself as being exactly the same as I was at 15. I think I have a general innocence about me, I guess. This is further proved by the fact that complete strangers will apologize for using swear words in my presence
As far as I know my voice doesn't sound young, though, I've always had kind of a deep voice for a female
I like it when people think I am younger that I am, though. I am one of those kids who never wanted to grow up and am still a kid in several ways. I'm flattered when they think I am a teenager.
Hopefully this trend will continue as I age.
*EDIT* I just saw this from above:
Livia wrote:
I don’t know whether it has anything to with AS, though, although my mum says that half of the reason why I’m mistaken for being a lot younger than I am is due to my posture, mannerisms, and my almost-permanent ‘scared’ expression, like I’m going to burst into to tears even if the thoughts running through my brain are ‘lalalalalalala! [pause] Ooo! Chocolate!”
I think this exactly why it
does have to do with AS. There is a general trend that aspies tend to look younger but I think the body language has a lot to do with how people perceive you. And, of course, an aspie would be the prime candidate for giving off the wrong non-verbal cues
I think we also tend to be less into social convention so more accepting of "childish" behavior and interests than regular society. This can also make us "young at heart."