I don't know why. A lot of boys are more affectionate than girls and you don't have to fear a son getting pregnant.
A load of crap that 'boys are more affectionate.' This is just an old wives tale created by people who have only sons and wanted daughters, to make themselves feel better about having no daughters...
As a pp said, it depends on the child, and how the child is treated/loved etc.... My girls are 2 of the most loving, affectionate, cute, funny, intelligent, caring human beings on the planet.. No sons could have been more affectionate.
As for the 'boys cannot get pregnant' line. What a joke. So boys 'can't get pregnant,' but they can still get a GIRL pregnant, and end up with EIGHTEEN YEARS of child maintenance tied to them, whilst having an almost non-existent relationship with the baby. And as for the grandparents of the boy's child (that he has with a woman who he splits up with;) forget it...... your 'grandchild' will know the postman better than he/she will know you.
Also find that adult daughters care a lot more about their parents/family... Mine have arranged weekends away for me and DH for our anniversary, and parties and meals out for our birthdays. They also visit us a minimum of 4-5 times a month... People I know with adult sons are lucky to get a birthday card off them, and a visit once every 3 months... In addition, the adult daughters of a couple of elderly people I know, visit far more often, administer more care, and take them out a lot more. The sons generally cannot be arsed.
Sounds like I am generalising? I am not. I am saying it like it is. In the majority of families I know, the adult daughters are much closer to the parents, and do far more for them, than the adult sons...
It cannot be easy having negative comments about having boys only, from people you know, but when people who DO have boys only see fit to lay into girls, and berate them, and say how much 'better' boys are, it really boils my piss. Seems like they are trying to convince themselves...........