This March 5, 1981, file photo shows John Phillips of the pop group "The Mamas and The Papas," left, and his daughter MacKenzie, right, shown during a taping of the John Davidson Show in Burbank, Calif. Phillips says she had a long-term sexual relationship with her father, John. People magazine says Phillips writes in her new book, "High on Arrival," that she had sex with her father on the night before she was to get married in 1979. Story here. (AP Photo/File)

Question: What do you make of this tell-all revelation?