Saturday night was a poignant event for the royals as they attended the Festival of Remembrance, an event dedicated to servicepeople who have served and lost their lives from Britain and Commonwealth nations.
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Prince William was one of the senior royals at the event, and he looked incredibly smart at the event wearing a black suit, alongside his service medals and a poppy. One striking part of his uniform was the red and black tie that he wore, and it's an item that the Prince of Wales has worn before.
WATCH: Royals arrive for the Festival of Remembrance
In fact, the father-of-three wears the same tie every year for the poignant ceremony as it is the regimental tie of the Household Division.
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During his career in the military, William served in their Blues & Royals regiment, so the item is a touching tribute.
The Prince and Princess of Wales put on a united front at the poignant event. Princess Kate sported her trademark three poppies on the lapel of her jacket, which are thought to honour her family members who have fought and died in wars.
William wore the special tie
Princess Kate's great-grandmother had three brothers who were killed in action during the First World War, however, the reason for the mother-of-three wearing multiple poppies has never been confirmed by the palace.
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This year's event bore special significance for the royals as it was the first to be held since the death of the Queen, who had been the Royal British Legion's patron and the longest serving Commander-in-Chief of the British Armed Forces.
The night marked the first time since 2006 that all working royals attended the Festival. Last year, most royals attended with the exception of Prince Andrew, who had stepped back from all public duties, and the Queen, who was forced to cancel her appearance upon her doctors' orders.