Why do some people think everyone needs one of each gender?

I get so annoyed when people assume everyone wants one of each gender and if they happen to get 2 of each instead of one of each that it's a disappointment. .. and then God forbid they try for a 3rd... they must only be trying for the gender they don't have. I have 2 girls... I'll be happy with either but a 3rd girl would be easier as our house is small and they will share a room (but obviously that's a minor bump in the road and we will figure something out if we have a boy) Anyway I find it rude for how many people actually ask "so do you think you'll try for a boy?" NO I hope to have a 3rd but the gender isn't an issue that even a little bit factors into ttc a 3rd... I remember my mil actually commented when I was pregnant with my second that "hopefully you have a boy then you can be done" ummm I think that's up to me to decide when I'm done but really?!

Anyway I know there are stupid people who make inappropriate comments about ttc and pregnancy with a lot of none of your business issues but this one really gets to me.

When we do ttc this December I hope when it happens (fingers crossed) that the 1st trimester is good to me and I can just keep it a secret for as long as possible...