Before DS2 was born I thought I didn't really want any daughters but I surprised myself after DS2 was born by feeling very sad that I would never have one. I actually found myself tearing up in shopping centres when I saw mothers and daughters (especially older daughters) shopping together. I don't really feel sad that I will never have a little girl but I do sometimes feel sad that I will never share the bond that my mother and I had when I was older with a daughter of my own. I also feel kind of sad that I will never be able to pass all my jewelry to my own daughter.
I certainly don't feel enough yearning for a daughter to go back and try for number 3 although for a while I wanted to.
TBH it would cause a lot of stress in my marriage if we had a daughter. DH is Afghan and whilst he's ok with a pretty non-traditional wife I think he would revert to type if he had a daughter. He might surprise me but I don't really want to put it to the test.