The Urban Institute and Migration Policy Institute, in a co-authored Sep. 2015 report, "Implications of Immigration Enforcement Activities for the Well-Being of Children in Immigrant Families," available at urban.org and migrationpolicy.org, stated:

“An estimated 5.3 million children live with unauthorized immigrant parents, and 85 percent of these children are US-born citizens…

[T]here were a total of 2 million formal removals from the United States and another 1.8 million deportations without formal removal orders [from 2009-2013]. Data on parental removals during this period are limited, but suggest that as many as half a million parents may have been deported, affecting a similar number of US-citizen children.”

Sep. 2015