Paris Hilton's (search) mom found the raunchy sex tape of her daughter painful, but said it taught her a lesson.

Kathy Hilton, speaking of the tape shot by the sex kitten's ex-boyfriend, told Newsweek magazine, "Well, that was very painful. Very painful. Very painful."

But, she said, "it taught me you can't trust everybody," she said, without identifying whom she no longer trusts.

The mom also said she had to be convinced to use the Hilton name in the title of the new NBC reality series, "I Want to be a Hilton." (search) In it, the moneyed matriarch's task is to transform a string of losers into believable upper-class Hiltons.

"The minute the Osbourne thing came out, everybody started calling us wanting to do something with the family, and we said, 'No. No. No,' " she said, referring to the hit MTV show about aging rocker Ozzy Osbourne and his family.

"We thought [using the Hilton name] was too cheeky," added Paris' dad, Rick.

Paris confesses she once thought it was cute to play a dumb blonde.

"On TV, I do it because it is funny. I consider myself a businesswoman and a brand."

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