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Citing "irreconcilable differences," the parents of Twilight mega-star Kristen Stewart are heading for divorce.

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According to documents obtained by ETonline, Jules Stewart filed a petition for divorce herself (without a lawyer) on August 17 in Los Angeles, stating that she and her husband of 27 years, John Stewart, have been estranged since June 15, 2010.

The news comes a little more than a month after daughter Kristen was caught, and later admitted to, cheating on boyfriend Robert Pattinson with her Snow White and the Huntsman director Rupert Sanders.

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Both of Kristen's parents work in the film/ TV business-- John produces for television and Jules writes/directs.