Robert F. Kennedy Jr. and Mary Kennedy

Robert F. Kennedy Jr.'s estranged wife Mary Kennedy was found dead Wednesday, TMZ.com reports. She was 52.

Kennedy was found in her Mount Kisco, N.Y. home after police responded to investigate a possible "unattended death," which means no one was there to witness her passing.

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Mary was Robert's second wife, whom he wed in 1994. The couple had four children before Robert filed for divorce in May 2010. Mary was reportedly arrested on suspicion of driving under the influence just three days after he filed papers.

Robert, who is reportedly linked to Suburgatory actress Cheryl Hines, is the son of former senator Robert Kennedy and the nephew of President John F. Kennedy.