As the royal family marked the first Remembrance Day since Queen Elizabeth's death, Kate Middleton was keeping the historic monarch close.

The Princess of Wales attended the Festival of Remembrance at London's Royal Albert Hall on Saturday alongside her husband Prince William, the Prince of Wales. Like the other royal women, Kate opted for a black ensemble for the solemn event paired with some meaningful jewelry. She wore two pieces that once belonged to her late grandmother-in-law: the Bahrain pearl drop earrings and a four-strand pearl choker necklace with diamond piece in the center.

Queen Elizabeth wore the choker necklace for a state banquet in Bangladesh in 1983, while the Bahrain Pearl Drop Earrings were a gift to the Queen for her wedding to Prince Philip in 1947.

According to Her Majesty's Jewel Vault, the earrings were made from a shell containing seven pearls gifted to Queen Elizabeth from the ruler of Bahrain for her wedding in 1947. The earrings contain a large round diamond with a smaller circle diamond hanging below it. Three baguette diamonds hang from there, with three more small diamonds making their way to the dangling pearl.

In September, Kate chose the same pieces to wear for Queen Elizabeth's state funeral and committal service.

The Princess of Wales previously wore the choker as well as the earrings for the funeral of Prince Philip in 2021. She was also recently seen in the pearl drop earrings at the Queen's Platinum Jubilee celebrations in June.

"Pearls are one of the very few jewelry items you can wear in mourning and are inextricably linked with Queen Elizabeth and her personal jewelry legacy," Bethan Holt, author of The Queen: 70 Years of Majestic Style, previously told PEOPLE. "It's a symbol of mourning a monarch but also a grandmother or great-grandmother."

Wearing pearls in mourning is a tradition set by Queen Victoria following the death of her husband Prince Albert in 1861, after which she wore black until the day she died. Queen Victoria accessorized with colorless jewelry, often pearls, which she loved and thought more appropriately discreet and respectful than sapphires, rubies or other colored gemstones.

At the Festival of Remembrance, Kate also accessorized her outfit with three red poppy pins. The artificial red flower has been used since 1921 to commemorate military members who have died in wars.

Princess Kate opted to wear three poppies on her otherwise black ensemble, which are believed to honor her great-grandmother Olive Middleton's three brothers, who all fought and died in World War I.

The Festival of Remembrance was also attended by King Charles and Queen Camilla; Prince Edward and Sophie, Countess of Wessex; Princess Anne and her husband, Vice Admiral Sir Tim Laurence; The Duke and Duchess of Gloucester; The Duke of Kent and Princess Alexandra.

The royal family has played a central role in the Remembrance Day commemorations since Queen Elizabeth's grandfather, King George V, laid the Unknown Warrior to rest in Westminster Abbey on November 11, 1920. He unveiled The Cenotaph war memorial later on the same day.

"The royal family is showing gratitude for the loss of life basically occurring in their name — certainly in the name of the sovereign as the head of state," A Century of Remembrance author Laura Clouting, referencing the British military oath.

She added, "Remembrance is very, very personal for them."