I take it this is your first? First congrats on already being a 20 week old father! We chose not to know for our first. Actually, never had an ultrasound so I guess that help us not knowing!
For our second, Joshua, there were thought to be complications so they had an ultrasound done. We were told that they were 95% sure he was a girl. So, prior to heading to the hospital, we asked Annie if she wanted to have Allison with one L or two.
I was pleasantly shocked when he came out all boy

. When I got home I said, "Annie, guess who's here?" She reply is it Allison? I said nope, it's Joshua. She started crying saying "I don't want Joshua, I want Allison."
Sometimes not knowing can be an asset!
Brian