Duchess Kate, Prince William and Prince Harry Celebrate Queen Elizabeth’s 70th Wedding Anniversary

Prince Harry Kate Middleton Prince William wedding anniversary dinner
Prince Harry, Kate Middleton and Prince William arrive at Windsor Castle to attend Queen Elizabeth II's and Prince Philip's 70th wedding anniversary dinner on November 20, 2017 in Windsor, England. Max Mumby/Indigo/Getty Image

A royal celebration! Pregnant Duchess Kate stepped out with husband Prince William and brother-in-law Prince Harry on Monday, November 20, for a very special occasion – to celebrate the longest marriage in British royal history.

Kate Middleton Prince William wedding anniversary dinner
Kate Middleton and Prince William arrive at Windsor Castle to attend Queen Elizabeth II’s and Prince Philip’s 70th wedding anniversary dinner on November 20, 2017 in Windsor, England. James Whatling/MEGA

They joined family and friends at Windsor Castle that evening in honor of Queen Elizabeth and Prince Philip’s milestone 70th wedding anniversary. Prince Charles was also there to toast his parents along with his siblings Princess Anne, Prince Andrew and Prince Edward.

Kate, 35, Harry, 33, and William, 35, were spotted sitting side-by-side in a black car on their way to the celebration. One familiar face that was noticeably missing was Harry’s girlfriend, Meghan Markle.

Queen Elizabeth II Prince Philip platinum wedding anniversary
Queen Elizabeth II and Prince Philip, Duke of Edinburgh pose for a photo in the White Drawing Room at Windsor Castle in celebration of their platinum wedding anniversary on November 20, 2017 in Windsor, England. Matt Holyoak/CameraPress/PA Wire via Getty Images

Kate, who is expecting her third child with William, stunned in a black lace dress, pearls and a huge smile. The royal brothers both donned black bow ties.

As previously reported, the Duchess had been keeping a low profile for the first 14 weeks of her pregnancy while suffering from severe morning sickness called hyperemesis gravidarum. “It was a difficult start to the pregnancy,” an insider explained to Us Weekly in October. “She is feeling significantly better, especially when you compare to how bad she was at the start. It was a worrying time for everyone.”

The royal couple announced their exciting news on September 4: “Their royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child,” Kensington Palace said in a statement at the time. “The Queen and members of both families are delighted with the news.”

The pair are already parents of Prince George, 4, and Princess Charlotte, 2.

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