“Incarceration breaks up families, the building blocks of our communities and nation,” says the report. “It creates an unstable environment for kids that can have lasting effects on their development and well-being.”

The vast majority of incarcerated parents are men. The number of children with fathers in jail or prison rose 500 percent between 1980 and 2000, according to the report.

But the number of children with mothers behind bars more than doubled between 1991 and 2007, four times the rate of growth in the number of kids with incarcerated fathers during the same time span.

And the effect of having an incarcerated mother is even more profound, creating more of a likelihood that the children will be placed with family friends, relatives or in foster care, and more likely that they will drop out of school.

The Casey Foundation is hoping to spark a discussion on how to give kids of incarcerated parents a better chance to succeed in life.