Nontraditional "Families" More Likely to be Abusive

This article makes the case.

(...) many scholars and social workers who monitor America's families see the abusive-boyfriend syndrome as part of a broader, deeply worrisome trend. They note an ever-increasing share of America's children grow up in homes without both biological parents, and say the risk of child abuse is markedly higher in the nontraditional family structures.

“This is the dark underbelly of cohabitation,” said Brad Wilcox, a University of Virginia sociologist. “Cohabitation has become quite common, and most people think, 'What's the harm?' The harm is we're increasing a pattern of relationships that's not good for children.''

(...)

-Children living in households with unrelated adults are nearly 50 times as likely to die of inflicted injuries as children living with two biological parents, according to a study of Missouri data published in the journal of the American Academy of Pediatrics in 2005.

-Children living in stepfamilies or with single parents are at higher risk of physical or sexual assault than children living with two biological or adoptive parents, according to several studies co-authored by David Finkelhor, director of the University of New Hampshire's Crimes Against Children Research Center.

-Girls whose parents divorce face significantly higher risk of sexual assault, whether they live with their mother or father, according to research by Robin Wilson, a family law professor at Washington and Lee University.

“All the emphasis on family autonomy and privacy shields the families from investigators, so we don't respond until it's too late,”