I was browsing Twitter the other day when I saw this post about Gender Disappointment. I actually could very much relate to her post. Now, I wasn't told that my child was supposed to be a boy when she really was a girl, all of my ultrasounds were very accurate with both of my kids. However, after having a healthy girl already, I was hoping that my second was a boy. I wasn't disappointed that she was a girl, I was disappointed that my intuition was wrong in the first place! (I usually have very good intuition.)
Many people do experience the "gender disappointment" however. This was so in the case of my ex fiance. He wanted a boy so badly that he could teach to drag race, play soccer and so on... When he found out she was a girl he was very upset. (He actually told me he didn't want to be a father since she wasn't going to be a boy. Hence why we are not together right now.) I'm sure that is a way extreme case of "gender disappointment", but I'm sure it still happens.
Especially when you have one child already of a certain sex, sometimes you may want the opposite sex for your second child, or third child or so on. It's normal to feel like you want one more than the other; it happens all of the time! We definitely should be happy that we are blessed with a healthy baby, but we all have our hopes and wishes.
Funny story: When my oldest found out I was pregnant she was unsure how to feel about it. (She was 2 at the time, though! Still my little baby!) I asked her if she wanted a baby brother or sister and she told me... "I want a penguin instead. Not a sister or a brother.". That's more like species disappointment than gender disappointment! All through my second pregnancy, my oldest wished for a penguin. She asked me after every appointment if I was sure I wasn't having a penguin for her. lol Thankfully, she loves her sister more than life! (And also still loves penguins. She hasn't gotten a penguin yet, we don't live in Alaska...)