Prince William Speaks Out About Kate's Severe Morning Sickness

Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge leave the King Edward VII hospital where she has been treated for extreme morning sickness at King Edward VII Hospital in London on December 6, 2012 -- Getty Premium

Prince William stepped out on Saturday night for the Winter Whites Gala in London -- his first public appearance since the hospitalization of wife Kate (and subsequent pregnancy announcement).

According to gala-goers, the Prince managed to crack a joke about the otherwise serious situation.

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"[William] said they shouldn't call it morning sickness as it's a day and all night sickness," Michael O'Higgens (former chairman of Centrepoint charity, who attended the event) told reporters of the Prince's remarks, via People.

While the Prince kept his engagement at the gala, he was also scheduled to attend the British Military Tournamant at Earl's Court in London on Sunday, but has canceled his appearance in order to spend time "privately with the Duchess," a spokesman for the royal couple said in a statement to the mag.

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"It is well known that hyperemesis gravidarum often recurs and, until further notice, to allow the Duchess a degree of privacy during her pregnancy, we do not intend to offer regular condition checks or advise of routine developments associated with it," the spokesman added.

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