Kate Middleton tiara
Kate Middleton wore the late Princess Diana’s tiara at an event at Buckingham Palace. Pictured from left: Camilla, the Duchess of Cornwall, Prince Charles, Queen Elizabeth, Prince Philip, Prince William and Middleton at the Diplomatic Corps at Buckingham Palace on Dec. 8, 2016 in London. Getty Images

Kate Middleton looked like a, well, princess in a new family portrait with her husband Prince William and other members of the royal brood. The Duchess of Cambridge joined the famous British royal family for an elegant reception dinner wearing a gorgeous red gown and diamond tiara.

According to the Us Weekly, the tiara Middleton was photographed wearing is known as the Cambridge Lover’s Knot and was a favorite of the late Princess Diana. The stunning headpiece features swinging pearls from 19 diamond-encrusted arches.

The outlet reported that Queen Elizabeth inherited the tiara from her grandmother Queen Mary and gave it to Princess Diana as a gift when she married Prince Charles in 1981. Princess Diana was spotted several times wearing the tiara at special events, but it was eventually returned to the queen after her divorce from Prince Charles in 1996. Princess Diana, who’s the mother of Middleton’s husband and his brother Prince Harry, died the following year in a car crash.

Middleton wore the diamond tiara, which she paired with diamond earrings and a dress designed by Jenny Packham, for a dinner the royal family hosted at Buckingham Palace Thursday for the world’s diplomatic corps and ambassadors. Also in attendance for the event was Prince William, Queen Elizabeth II, her husband Prince Philip, Prince Charles and his wife Camilla, the Duchess of Cornwall.

Vanity Fair reported that this is the second time the Duchess of Cambridge has worn the Cambridge Lover’s Knot. The first time was at the same event last year. The 34-year-old mother of two also recycled the Jenny Packham gown she wore. According to the Telegraph, she was spotted in the stunning dress last year at the State Banquet for President Xi of China at Buckingham Palace.