Kate Middleton, Prince William, King Charles III and senior members of the British royal family gathered in Gloucestershire over the weekend to celebrate the marriage of Peter Phillips and Harriet Sperling, but the event also revived interest in a little-known chapter of the Princess of Wales's life long before she became a future queen.

Among the guests attending the wedding was Rupert Finch, a former University of St. Andrews classmate who briefly dated Middleton more than two decades ago. The appearance of both Finch and the Princess of Wales at the same family celebration drew attention from royal observers, largely because public discussion of Middleton's relationships before Prince William has remained relatively rare.

The ceremony, held at All Saints Church in Kemble, brought together many of the most recognizable figures in the royal family. King Charles, Queen Camilla, Princess Anne, Zara and Mike Tindall, along with the Prince and Princess of Wales, were among those attending the wedding of Peter Phillips, Princess Anne's son and the late Queen Elizabeth II's eldest grandson.

For Middleton, the event marked another high-profile public appearance following her gradual return to royal duties after cancer treatment. Dressed in a beige Roland Mouret ensemble, she arrived alongside Prince William as photographers documented one of the largest royal gatherings of the year.

Finch attended with his wife, Lady Natasha Rufus Isaacs, whom he married in 2013. While the encounter between Middleton and her former boyfriend generated headlines, those familiar with royal history note that the relationship itself was brief and occurred years before Middleton's romance with William began.

Middleton and Finch reportedly dated in 2001 while studying at the University of St. Andrews in Scotland. At the time, Middleton was beginning university life, while Finch, described by Tatler as a "tall, dark, and handsome aspiring lawyer," was further along in his studies.

The relationship ended long before Middleton's life became intertwined with the monarchy. Within a few years, her friendship with Prince William evolved into a romantic relationship that would eventually become one of the most closely scrutinized courtships in modern royal history.

Much of the public fascination surrounding Finch stems from how little has been said about that period. Unlike many figures connected to the royal family, Finch has consistently declined to discuss the relationship publicly.

"It's not something I'll ever talk about. It's between Kate and me and was a long time ago," Finch previously said.

That discretion has largely defined the way both parties have handled the subject. While royal biographies and media reports occasionally revisit Middleton's university years, neither she nor Finch has publicly elaborated on their brief relationship.

The years since have taken both lives in dramatically different directions. Middleton married Prince William at Westminster Abbey on April 29, 2011, in a ceremony watched by millions around the world. The couple now share three children-Prince George, Princess Charlotte and Prince Louis-and remain central figures in the monarchy's future.

Notably, Finch himself attended William and Middleton's royal wedding in 2011, a detail often cited by royal commentators as evidence that any personal awkwardness had long since faded. His inclusion at one of the most significant events in modern royal history suggested cordial relations had been maintained despite their shared past.

Middleton and William recently celebrated their 15th wedding anniversary, sharing a family photograph accompanied by the message: "Celebrating 15 years of marriage." The milestone reflected the stability of a relationship that has endured intense public scrutiny while evolving into a cornerstone of the modern monarchy.

Meanwhile, Finch and Lady Natasha Rufus Isaacs have built their own family life and are parents to three daughters: Georgia, Cienna and India.