Have you heard of the Longevity Project? It was started in 1921 by Stanford University psychologist, Lewis Terman, who pulled 1,500 young, bright children from their classrooms and interviewed them about pretty much everything. These kids were then followed throughout their life, many outliving Terman, and the research was picked up by Howard Friedman and Leslie Martin. Looking at this unprecedented amount of data, Friedman and Martin asked, "Could the child's experience of divorce be related to mortality risk many years in the future?"
The two compared the mortality rate of children whose parents had divorced to those who had lost a parent through death. In terms of an individual's lifespan, they found that it's actually better for your parents to die than for them to divorce! In fact, they found no life-long negative impact from death, whereas on average, children of divorced parents lived roughly five years less. Moreover, parental divorce during childhood was the single strongest social predictor of early death, many years into the future. I guess staying together is good for the kids. For more, read this Psychology Today column.