Update 2012-10-03: Another interpretation of these graphs would be that people tend to have kids 1-3 years after getting married and the happiness bump we're seeing is mostly that people really like the first few years of marriage.
Update 2012-10-03
Update 2012-10-03: Another interpretation of these graphs would be that people tend to have kids 1-3 years after getting married and the happiness bump we're seeing is mostly that people really like the first few years of marriage.