Kate Middleton’s Decision to Wear Three Poppy Pins Instead of Just One Is Deeply Personal

It’s a tradition she began years ago and has continued, including at Nov. 10’s Remembrance Sunday event at The Cenotaph

Kate Middleton wore three poppies pinned to her black Catherine Walker ensemble for Remembrance Sunday — and there’s a meaningful reason why.

The Princess of Wales, 42, made back-to-back appearances on Nov. 9 and Nov. 10, first at the Festival of Remembrance at Royal Albert Hall on Saturday night and then, on Sunday morning, at Remembrance Sunday at The Cenotaph war memorial. This marked a big step in Princess Kate’s gradual return to royal life, which began after she announced on Sept. 9 that she had completed chemotherapy, roughly six months after she announced on March 22 she had been diagnosed with cancer.

As she stood on the balcony of the Foreign Office building with Sophie, Duchess of Edinburgh, Kate wore three poppy pins affixed to her coatdress. While many members of the royal family stuck with just one, Kate’s choice to wear three had a symbolic meaning: they honor her great-grandmother’s three brothers, all of whom died in World War I, according to The Daily Mail.

According to The Mirror, Kate had the chance to view letters from her ancestors during an “emotional visit” to the Imperial War Museum in 2018. Kate began wearing three poppy pins to Remembrance Sunday as far back as 2015, having worn one just the year before, according to The Sun. She continued to wear the set of three every year until 2019, when she opted to wear the Codebreakers brooch in honor of her grandmother, Valerie Glassbarrow. In 2020, Kate went back to the set of three poppies, this time accessorizing them with the Royal British Legion crystal flower.

Remembrance Sunday takes place on the second Sunday of November every year and is a national commemoration to remember the members of the Armed Forces across the U.K. and Commonwealth who lost their lives in conflict or war. Kate has never missed Remembrance Sunday since marrying into the royal family in 2011.

Related: Why Do Members of the British Royal Family Wear Red Poppy Pins in November?

The poppy has been used since 1921 to commemorate military members who have died in wars. The red flower is mostly associated with the U.K. and Commonwealth countries for Remembrance Day on Nov. 11, and the poppy symbol is believed to have come from the poem “In Flanders Fields” by John McCrae, a poem about World War I.

The royal’s Nov. 10 outfit was loaded with symbolism, even beyond the three poppies. She wore a coatdress from Catherine Walker, a tribute to her late mother-in-law Princess Diana, who counted Walker as her favorite designer and a personal friend. The night before, at the Festival of Remembrance, Kate paid another sartorial tribute to Diana, as she wore her Collingwood pearl earrings to the occasion.

Related: Kate Middleton Poignantly Honors Late Mother-in-Law Princess Diana Two Days in a Row at Remembrance Events

On Nov. 10 at Remembrance Sunday, Kate wore a pair of Bahrain Pearl Drop earrings that were a gift from Queen Elizabeth, who received the earrings as a wedding present when she married Prince Philip on Nov. 20, 1947. (The Princess of Wales wore the same meaningful earrings to the late Queen’s funeral in September 2022.)

Queen Elizabeth, like Kate, also chose to wear more than one poppy — the late monarch wore five poppies, one for the Royal Navy, the Royal Marines, the British Army, the Royal Air Force and the Defense Medical Services.

Other working royals at The Cenotaph alongside Kate and Sophie were King Charles, Prince William, Prince Edward, Princess Anne, Vice Admiral Sir Timothy Laurence, Prince Richard, the Duke of Gloucester, Birgitte, the Duchess of Gloucester and Prince Edward, the Duke of Kent.

Queen Camilla was absent from this weekend’s Remembrance events, missing both events on Nov. 9 and Nov. 10  as she continues to recover from a chest infection. On Nov. 9, the palace released a statement confirming her absence that said, “Following doctors’ guidance to ensure a full recovery from a seasonal chest infection, and to protect others from any potential risk, Her Majesty will not attend this weekend’s Remembrance events.”

“While this is a source of great disappointment to The Queen, she will mark the occasion privately at home and hopes to return to public duties early next week,” the statement continued.

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This weekend marked a big step forward in Princess Kate’s gradual return to public duty, which is expected to continue in December with her annual Christmas carol concert at Westminster Abbey. In her emotional Sept. 9 video announcing she’d completed chemotherapy, she said in part, “Doing what I can to stay cancer free is now my focus. Although I have finished chemotherapy, my path to healing and full recovery is long and I must continue to take each day as it comes.”

“I am, however, looking forward to being back at work and undertaking a few more public engagements in the coming months when I can,” she added. She’s kept true to her word, attending both private and photographed meetings at Windsor Castle around some of her key causes and stepping out with the Prince of Wales in Southport, England on Oct. 10 ahead of her Remembrance appearances over the weekend.

“She is clearly a vital piece of the royal family, really important both symbolically and in reality as a future Queen,” royal biographer Sally Bedell Smith tells PEOPLE. “It was good that people saw her. You can’t say she is back … but she is coming back.”

“Being a senior member of the royal family and doing these ceremonial events is obviously important to her,” Bedell Smith adds.