The first one hits marital satisfaction hard.
An eight-year study of 218 couples found 90 percent experienced a decrease in marital satisfaction once the first child was born.
“Couples who do not have children also show diminished marital quality over time,” says Scott Stanley, research professor of psychology at University of Denver. “However, having a baby accelerates the deterioration, especially seen during periods of adjustment right after the birth of a child.”
A new study shows that raising [children] is a lifelong challenge to your mental health.
Not only do parents have significantly higher levels of depression than adults who do not have children, the problem gets worse when the kids move out.
“Parents have more to worry about than other people do—that's the bottom line,” said Florida State University professor Robin Simon. “And that worry does not diminish over time. Parents worry about their kids' emotional, social, physical and economic well-being. We worry about how they're getting along in the world.”
“People should really think about whether they want to do this or not,” Simon said of parenting.
Neither study summary mentions the effect of having two children compared to one, or three compared to two, etc. It may be that once you've taken that big first step toward depression and marital dissatisfaction, the extra kid doesn't make things any worse. But if I were Bryan I'd be sure to track down this data and check it out.
[NB: I still want kids!]