My mother in law keeps calling our baby a boy?

I'm only 9 weeks along in my pregnancy, since 6 weeks my mother in law keeps calling our baby Travis, which is the name we picked out If it was a boy. It annoys me that she's calling our baby Travis already, because she doesn't know if it's a boy or a girl. My husband and I have no clue yet, so how would she know? She has only touched my belly ones. Am I being dumb for getting upset about her calling our baby Travis?