Looks like the Duke is missing his Duchess.

Making his first official public appearance since the Dec. 3 news that he and his wife are expecting a baby, Prince William stepped out sans Kate Middleton to attend the Winter Whites Gala at London's Royal Albert Hall on Saturday, Dec. 8.

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The dapper Duke of Cambridge, 30, donned a double-breasted tux for the event, which aids Centrepoint, the homeless charity of which he is a patron. Noticeably absent? His pregnant wife, also 30, who was scheduled to accompany the prince but had to bow out earlier this week due to a condition known as hyperemesis gravidarum, an acute form of morning sickness.

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Middleton was admitted to London's King Edward VII hospital on Dec. 3, the same day St. James Palace announced her pregnancy. Though she has since been released, she was forced to cancel several upcoming appearances, including the Winter Whites Gala, the ICAP Charity Day on Dec. 5, and the British Military Tournament at Earl's Court, London, on Dec. 9. She is currently resting at Nottingham Cottage.

"Catherine is sad not to be at the event," a royal aide tells Us Weekly. "She was really looking forward to it."

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No doubt her husband was looking forward to having her there, as well. It's been a difficult week for the royal couple -- in addition to Middleton's hospitalization, they have also had to deal with the reported suicide of Jacintha Saldanha, who helped care for the Duchess at King Edward VII.

On Friday, Dec. 7, the 46-year-old nurse was found dead following an earlier incident in which she fell victim to a prank call from two Australian DJs and accidentally gave them access to confidential information about the pregnant royal.

This article originally appeared on Usmagazine.com: PICTURE: Prince William Attends Winter Whites Gala Without Pregnant Kate Middleton