I'm interested in the research regarding the happiness of mothers declining after having more than one child. On the one hand, this is not surprising, since having children is naturally stressful. On the other, you ask what made people chose to have more? I have three, and was aware that each child would add to the short-term stress, but intuitively, I felt that many years down the road, having more than one would ultimately pay off in happiness (through having larger family connections, more grandchildren, more kids to visit, and even (selfishly) take care of us, etc). I'm curious as if there are any long term 'happiness' studies that would confirm or deny that intuition.