The wife of comedian Robin Williams has filed for divorce, citing irreconcilable differences.

Marsha Garces Williams met the 56-year-old star when she was hired as a nanny for his child with previous wife, Valerie Valardi.

The couple married in 1989 and have two children. Their daughter, Zelda, is 18-years-old and they have a 16-year-old son called Cody, whom Mrs Williams is requesting joint custody for, according to the filing.

Mrs Williams filed her petition in a San Francisco court last week after nearly 20 years of marriage to the Hollywood star.

Documents show the pair have been separated since New Year's Eve.

The Oscar-winning actor is well known for family films such as Mrs Doubtfire and Jumanji, but has also won critical acclaim for his role in dramas, Good Will Hunting, Good Morning Vietnam, and Dead Poets Society.

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