The royal family were out in full force on Sunday, as they attended the National Service of Remembrance at The Cenotaph. It was King Charles' first as head of state, and amongst those in attendance was his uncle, the Duke of Kent.
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The 87-year-old was pictured observing the moving ceremony from the balcony of the Foreign Office, alongside Princess Anne's husband, Sir Tim Laurence.
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The Duke of Kent wore his military uniform, but royal fans were quick to notice his coat was missing a button.
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READ: Why this year's Remembrance Festival was extra special for the royal family
It's not the first time the Queen's cousin has suffered a wardrobe mishap.
The Duke's coat appeared to be missing a button
Earlier this year, the Duke attended Trooping the Colour wearing his Order of St Michael & St George Sash on the wrong shoulder.
The Duke of Kent wore it from his left shoulder to his right hip, when it should be worn from his right shoulder to his left hip.
It seems the royal confused his sash with the Order of Garter Sash, which he normally wears to Trooping and goes on the opposite shoulder.
The Queen pictured alongside the Duke, who wore his sash incorrectly earlier in June
Many more royals attended the special day, including the Prince and Princess of Wales, Prince Edward and the Countess of Wessex, as well as Princess Anne.
It was a particularly special day for Princess Kate, as not only did she debut a stunning new brooch, most likely a birthday gift from the royal family earlier this year, but she signed the heartfelt note on William's wreath alongside her husband for the first time.
The couple's signatures appeared underneath a heartfelt message penned by Prince William. It read: "In memory of those who have made the ultimate sacrifice, we will remember them."
This was the first time that William has laid a wreath at the Cenotaph since his father acceded to the throne and he became Prince of Wales following the Queen's death.