“But at some point – a point I think we are well past, given the body of research – the
weight of the evidence is so strong that the most reasonable conclusion is that even
if there were some unobservable differences between single and married parents,
the thing staring at us from the data is overwhelming: having a second parent in the
home, with the added resources (money, time, etc.) that second parent brings, is, on
average, beneficial for children’s outcomes.”