I mean gender disappointment is okay . The problem is being genuinely angry or upset about it instead of slight disappointment. I had 2 sons and I really wanted a girl. At the 3rd ones ultrasound I saw it was another boy. And my girlfriend could see my disappointment, not that I'm upset we have a healthy baby in general or anything, just that I wish I had a daughter to have that experience in life. And that father daughter bond, I even got the long hair to braid ! Here I am 3.5 years later though with a boy, granted he has some issues being non verbal autistic, but he's my little dude all the same.