Paris Hilton's parents enjoy watching their daughter's sex tape

That's according to a new biography by Jerry Oppenheimer.

Jerry claims that while researching his book House of Hilton he found out that Paris ' parents, Rick and Kathy, were not fazed when One Night In Paris was leaked on the internet.

He said: "I have family sources telling me that Rick and Kathy Hilton are proud of everything Paris has done, including the X-rated video that launched her to this international stardom and infamy and fame.

"It is a bizarre family. Behind the scenes her parents were not opposed to the video because that totally launched her."

The author also says he ended up feeling sorry for The Simple Life star because her mother pressured her to become a celebrity.

Jerry said: "Kathy put her in make-up and allowed her into nightclubs from a very young age.

"I feel sorry for her because in a way she had no chance to do anything else but live the dreams that her grandmother and her mother had for themselves.

He added: "My goal in doing this book was to figure out how she became who she is. I came away feeling a bit sympathetic for her because I don't think she had a chance to do anything besides what she is doing."