Moffitt

But the good news is that, Moffitt says, self-control can be taught by parents, and through school curricula that have been proved to be effective.

Moffitt said it's still unclear why some children have better self-control than others, though she says other researchers have found that it's mostly a learned behavior, with relatively little genetic influence.

Speaking from New Zealand via Skype, Moffitt explained that self-control problems were widely observed, and weren't just a feature of a small group of misbehaving kids.

Terrie Moffitt of Duke University and her research colleagues found that kids with self-control issues tended to grow up to become adults with a far more troubling set of issues to deal with.