Well-wishers will always tell the Mother of the Bride: "You're not losing a Daughter...you're gaining a Son!" But in reality, she's not gaining a Son...she's losing a Daughter! Hal
However, there is the old saying: A son is a son til he takes a wife, But a daughter's a daughter the rest of her life. It's true that in the "olden days", a woman left her family to join her husband's family and quite often, her family never saw her again. These days, though, it's more often the wife who controls which side of the family gets the most visits, attention, interaction with the grandchildren, holiday attendance, etc. And that side is usually hers. It's nice, though, when both sides gain a daughter and a son.