Does this child have autism?

my sister has autism and when i talk to her [very rare that with people with autism can talk] i do have to ask her a few times...and even that she doesnt. alot of people with autism have a sincere things. and hers could be touching other people. i know a men who has to touch other people arms. my sister sincere is NOT to be touched lol. She gets really mad when you do it. Alot of autistic kids are socially awkward and dont have alot of friends. So to me it does sounds like she could.. but at the same time shes only 12 it could just be her being herself.