Gender mix ups

Amanda • Josiah 6/24/16 👶 10/15/16 💍 Nathan 6/14/18 👶 21 years old
I'm curious on this. I've heard of people being told it's a girl and it really being a boy. I haven't heard of someone being told it's a boy and it coming out a girl. Does this even happen? Has it ever happened to anyone here? Like I said I'm curious.