"That's completely false and I am very very surprised that he would come out with this type of accusation," Cox said. "I have been aware of my daughter's problems with Steven Powell -- she had told us a long time ago that he had made some advances toward her … told us that it made her uncomfortable, and that her husband didn't care. They decided to move to Utah and that was to get away from Steven."
Josh Powell also described his wife as flirtatious and mentally unstable when interviewed on "Good Morning America." He recounted an instance of her leaving the house in only her underwear, and described what he called a troubled childhood.
"Susan was very -- emotionally abused as a child. Her mother has some very … she has a very angry personality. Her father is very manipulative," he said.
When told of his father's revelation that he had a flirtatious and sexually charged relationship with his daughter-in-law -- and that it was typically initiated by her -- Josh Powell denied it, but also said that any flirtation has to do with his wife's nature.
"There was nothing like that. She's a very flirtatious person. But that's just her personality. You know, it's -- it's part of her friendliness," he said.
While he has not been arrested or charged in her disappearance, police said he continues to be considered a person of interest. He maintains his innocence.
"Everyone who knows me knows that I would never hurt her and I would never hurt my boys," Powell said. "I would never hurt anyone."