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Camille Mann /

CBS News/ January 9, 2013, 11:42 AM

Duchess Kate turns 31: How is she celebrating?

Britain's Catherine, Duchess of Cambridge, wife of Prince WiIliam, leaves the King Edward VII hospital in central London, on Dec. 6, 2012.

Britain's Catherine, Duchess of Cambridge, wife of Prince WiIliam, leaves the King Edward VII hospital in central London, on Dec. 6, 2012. / LEON NEAL/AFP/Getty Images

Mom-to-be Kate, Duchess of Cambridge is not celebrating her 31st birthday Wednesday with a big blow out, according to a report.

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Kate, Duchess of Cambridge

Instead, Duchess Kate is celebrating her birthday "privately," according to a rep for St. James's Palace told Us Weekly.

"She just wants something low-key," a source told the magazine. "I suspect she will spend it at her parents' house."

According to People, Kate will be reunited with her husband William, who was serving on a Royal Air Force search and rescue crew over the holidays.

Last year the duchess chose to celebrate her birthday in a similar "low key" fashion, having a private dinner with friends and family.

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