Contemplating whether or the number of children to have? Take a look at “A Global Perspective on Happiness and Fertility” by Margolis and Myrskylä. The authors use data from 25 years of the World Value Survey, totalling 86 countries and over 200 000 respondents. They are interested in what the relation between what people answer on the question “Taking all things together, would you say you are very happy, quite happy, somewhat happy, or not at all happy?” and their number of children.
Margolis and Myrskylä find that a higher number of children is associated with lower happiness, but stress that looking at this in the aggregate is highly misleading. This is shown by breaking the data down by subcategories and plotting the results. In particular, they “find that the association between happiness and fertility evolves from negative to neutral to positive above age 40,” as shown e.g. here:
So more children may pay off in the long run. Though it must be said that this is just descriptive, but valuable and interesting nevertheless. There are more graphs like this one, and the results can be understood simply by looking at the graphs.
With also the recent report that “economists with two or more kids tend to produce more research, not less, than their one-child or childless colleagues” in hand and just having achieved the second, I am expecting a short-term boost in productivity and long-term in happiness.