Royals Kate Middleton Makes Surprise Appearance Alongside Prince William to Mark Anzac Day Kate recycled a cream coat that she previously wore to Princess Charlotte's christening in 2015 By Stephanie Petit Stephanie Petit Stephanie Petit is a Royals Editor, Writer and Reporter at PEOPLE. People Editorial Guidelines Published on April 25, 2022 10:18 AM Share Tweet Pin Email Kate Middleton joined husband Prince William in honoring Australians and New Zealanders killed in war. To mark Anzac Day on Monday, Prince William attended a poignant service at The Cenotaph war memorial in London. He laid a wreath of poppies on behalf of his grandmother Queen Elizabeth. William, 39, then headed to Anzac Day Service of Commemoration and Thanksgiving at Westminster Abbey, where he was joined by wife Kate at their royal wedding venue. The Duchess of Cambridge, 40, recycled the cream coat dress she previously wore at Princess Charlotte's christening in 2015 paired with a halo headpiece. Both Kate and Prince William sported red poppy pins, an artificial flower that has been used since 1921 to commemorate military members who have died in war. Prince Louis Is All Grown Up in His 4th Birthday Photos — at the Beach! See All 4 Kate Middleton and Prince William. Eamonn M. McCormack/Getty Images The poppy symbol is believed to have come from the poem "In Flanders Fields" by John McCrae, a poem about World War I. The opening stanza reads: In Flanders fields the poppies blowBetween the crosses, row on row,That mark our place; and in the skyThe larks, still bravely singing, flyScarce heard amid the guns below. The royal family proudly wears their pins when they honor armed forces who sacrificed their lives. Kate Middleton. Alamy Stock Photo Anzac Day commemorates the first major battle involving Australian and New Zealand forces during World War I. It has been honored in London since the first anniversary of the Anzac landings at Gallipoli in 1916, when King George V attended a service at Westminster Abbey. Prince William. Chris Jackson/Getty Images Earlier in the day, the Queen's cousin Prince Richard, the Duke of Gloucester attended the Dawn Service at the New Zealand Memorial at London's Hyde Park Corner. Last year, Princess Anne represented the royal family at the Westminster Abbey service for Anzac Day after the event was canceled in 2020 due to the coronavirus pandemic. Kate and Prince Harry attended together in 2019, with Meghan Markle missed the event as she was nearing the end of her pregnancy with son Archie, born just a couple weeks later. Kate Middleton. Mark Cuthbert/UK Press via Getty Images Over the weekend, Kate and Prince William celebrated the fourth birthday of their youngest child, Prince Louis, by releasing four new portraits of the little royal. Taken earlier this month by Kate near the family's country home in Norfolk, the photos show Prince Louis playing on the sand. Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! Bearing a striking resemblance to both brother Prince George, 8, and sister Princess Charlotte, 6, Louis sprints in front of the camera with a smile on his face and playfully holds a cricket ball.