“1991 vs 2024: Two loving mothers at Wimbledon,” a fan blog captioned a side-by-side comparison of the photos on Instagram.

The royal moms’ outfits weren’t the only similarity. When Prince William went to Wimbledon with Princess Diana in 1991, he had recently turned 9, the same age his only daughter is now.

Prince William also joined his mom in the Royal Box though children traditionally aren’t allowed in the exclusive area.

Exceptions are made for British royal kids to join their parents there, and Prince William and Princess Kate’s eldest child, Prince George, also sat there during his two Wimbledon appearances in 2022 and 2023.

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Lady Diana Spencer, as she was known before her marriage to the future King Charles, was first photographed at Wimbledon in July 1981, just a few weeks before their royal wedding later that month. She attended again in 1987 and brought along Wiliam in 1991.

Princess Diana would return to Wimbledon most summers of the early 1990s, including another outing with Prince William in 1994.

Diana’s last appearance at the championship would be in 1995, and she and then-Prince Charles finalized their divorce the following year. She died in 1997 at age 36 following a car accident in Paris.

Decades later, Princess Diana’s daughters-in-law, Princess Kate and Meghan Markle, are known to pay homage to her iconic style through fashion and jewelry. Princess Kate, who became the new bearer of Diana’s title as the Princess of Wales as the wife of a male heir to the British throne, may have taken inspiration from her late mother-in-law by wearing purple at Wimbledon on July 14, marking her first time sporting the hue at the tennis tournament.

The bespoke purple dress also matched the green and purple bow tie pin that Kate wears to Wimbledon as patron of the All England Club. She did the same last year, wearing green for all three tournament appearances in perfect color coordination with her pin.

Bethan Holt, the Fashion Director at the Daily Telegraph, tells PEOPLE, “Kate has a history of choosing clever, whimsical themes for her Wimbledon looks, and this was a new one. Wearing purple underlines how important that role is to her and why she chose this event to make her second public appearance of the year.”

“It’s also the color of courage, which could be a nod to what she is going through,” she added.

While Wimbledon has long been a staple on Kate’s summer calendar, her outing at the 2024 tournament came as she continues treatment for cancer. The outing with her daughter and sister, Pippa Middleton, was only her second public appearance this year following Trooping the Colour on June 15.

The Princess of Wales announced in March that she was undergoing treatment for cancer and has been staying largely outside of the spotlight to privately prioritize her health in the months since.