As part of that study, in 1986:
[The researchers, including Block] examined members of the original group whose parents eventually divorced. Conducted with Professor Gjerde, the study upended the received wisdom that divorce in and of itself causes disruptive behavior in children.
Instead, the authors found, children from the divorced families — in particular the boys — had displayed antisocial behavior years before the divorce took place. In other words, the boys’ behavior, with the stresses on family life it entailed, could have been a cause of divorce as well as a consequence.