The secret revelation of Mackenzie Phillips and her incestuous relationship with her father, Mamas and Papas singer John Phillips, is one of the many reasons why UT history professor Lynn Sacco published her first novel Unspeakable: Father-Daughter Incest in American History in July 2009. Sacco said the book reveals insight into the issue, as well as discusses incest in America and its underlying causes.

Simply wishing incest didn't happen--or claiming that there is no way of knowing if it happened--won't stop father-daughter incest or protect vulnerable girls from assault. Lynn Sacco, author of Unspeakable: Father-Daughter Incest in American History

In her book, Sacco traces the acts of incest throughout American history through medical and social means. She said that Mackenzie Phillips' accusations could also reveal more insight into the debates about the hidden acts of girls during their childhoods.

Sacco said that at first, acts of incest were quickly stopped, but during the 1920s and 30s, most Americans began to believe that such an act would occur among upper class, Caucasian girls. She said this belief slowed the investigating process for many of them. To most people, incest only occurs among poor people, minorities or immigrants.

"Every time an allegation is made, people spend a lot of time debating whether it really happened," Sacco said. "Such debate is rather pointless. Simply wishing incest didn't happen--or claiming that there is no way of knowing if it happened--won't stop father-daughter incest or protect vulnerable girls from assault."

Although Sacco's novel does reveal some insight into the allegations between fathers and daughters, through it, she ultimately encourages that "more work be done to improve the work of girls in the society."