> Taken together, the results of these analyses suggest that ma- ternal employment early in a child’s life is not commonly associ- ated with decreases in later achievement or increases in behavior problems.

The other one says a similar thing. They both seem to say that for the first year or two having a stay at home parent is beneficial, but beyond that it doesn't really matter.

These seem like significant and durable results on how to raise a child beyond parental income