Don't have another baby because of what your friend says!
Your DS and DH are your family, and if that's what your family to be, then that's perfect!
I know someone, wouldn't call her a friend nowadays, we used to be, but her views are crazy!
She believes that boys are not "proper children", that anyone who has a boy is not a "real parent" and that anyone who has a boy must be desperately disappointed, if someone has a girl after having a boy first, she thinks that the parents must be over the moon "to have a girl after the disappointment of a boy" Also if it's the other way round, she thinks the parents must be devastated and regret having the other child.
Once she said to me after reading a story about IVF, and the parents had had a boy, "Imagine going through all that, only to have a boy"
She was very open with these views, I have no idea why she feels like this, it's beyond strange and offensive. She has one 12 year old DD, and said she wouldn't have "risked having another one in case it's a boy" 
I can't get my head round these views at all