Kensington Palace has released a heartwarming video documenting some of the key moments for the royal family in 2017 – but surprisingly Prince William and the Duchess of Cambridge's third baby announcement was not included in the montage. Royal fans were quick to notice that the pregnancy news was absent from the annual round-up, which was posted on the Palace's official Twitter account. Highlights in the footage include Prince George's first day at school, Prince Harry and Meghan Markle's engagement announcement, William and Kate's Christmas card release and the Duke of Cambridge's last shift as an air ambulance pilot.

Prince William and Kate will welcome their third child together in April

Fans were quick to remark on the omission in the comments section, with one writing: "How about Kate's pregnancy? Not a highlight?" A second said: "How could the Kensington Palace account make four of these year end retrospectives and not once include the fact that the Duke and Duchess of Cambridge are expecting in April?? What a strange oversight!!" A third added: "Interesting that they didn't mention the announcement that baby #3 was on the way…" Others, however, simply shared their delight after watching the slide show. "This was very nice! So many milestones for them in 2017! And 2018 will be full of even more love." Another agreed, writing: "What a perfect way to end 2017!"

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For our final highlights video, let's take a look back at some of the key family moments this year. pic.twitter.com/gwVftwrcso

— Kensington Palace (@KensingtonRoyal) December 31, 2017

The new year promises to be an exciting one for the royal family. In April, William and Kate will welcome their third child – a baby brother or sister for Prince George, four and Princess Charlotte, two. And on 19 May, Prince Harry and Meghan will marry at St George's Chapel, Windsor Castle, following their engagement announcement on 27 November.