Kate Middleton and Prince William share a kiss on the polo pitch in July 2023, like Princess Diana and then-Prince Charles did in June 1985.Photo:Samir Hussein/Getty, Tim Graham Photo Library/Getty

Royal Polo kisses

Samir Hussein/Getty, Tim Graham Photo Library/Getty

Kate MiddletonandPrince William’s PDA on the polo field calls back toPrincess DianaandKing Charles’ kisses on the pitch.

The Prince and Princess of Wales, both 41, shareda rare public kissat theRoyal Charity Polo Dayat Guards Polo Club on Thursday, smooching each other on both cheeks before Prince William collected his trophy. The embrace was evocative of the PDA his parents shared on the polo field decades earlier, as Diana would similarly support then-Prince Charles at his polo matches during the years of their marriage. The couple would often kiss at the events — sometimes on the lips!

While Prince William and Princess Kate’s latest public display of affection might be an unusual sight, royal etiquette expert Myka Meierpreviously told PEOPLEthat there are no formal rules on royal couples showing romance in public — it’s at their own discretion.

Princess Diana and Prince Charles share a kiss on the polo pitch in June 1985.Tim Graham Photo Library/Getty

Royal Polo kisses

Tim Graham Photo Library/Getty

“Senior members of the royal family would likely not be told how to interact or when they can or can not show PDA and would be trusted to use their better judgment as to when it’s appropriate,” the founder and director ofBeaumont Etiquettesaid. “The royals often adjust PDA to mirror the formality of the event they are attending. At a somber or more formal event, we are less likely to see PDA than at a casual event where it would be deemed more fitting.”

While the Royal Charity Polo Day is technically an official event for Prince William and Princess Kate, as the charity match raisesmillions of dollarsfor causes close to their hearts, the two seem to be more relaxed with affection in the sporty setting as compared to more formal engagements.

Kate Middleton and Prince William at the Royal Charity Polo Cup in 2022.Chris Jackson/Getty

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge embrace after the Royal Charity Polo Cup 2022 at Guards Polo Club during the Outsourcing Inc. Royal Polo Cup at Guards Polo Club, Flemish Farm on July 06, 2022 in Windsor, England.

Last year, the couple shared a similarcongratulatory kissat the polo match and walked with their arms linked around each other’s backs.

While the Prince and Princess of Wales (the future king and queen!) typically refrain from PDA, they have had a few sweet moments at events in recent months. During the celebration of King Charles' coronation in Scotland on Wednesday, Kate wasspotted with her hand on William’s backsideas she leaned over to chat with him. The touch wasreminiscent ofanother love tap between the royal couple at the BAFTAs in February — as the royal couple walked the red carpet, cameras caught a blink-and-you’ll-miss-it moment where Kate patted William’s butt.

Prince William and Kate Middleton in Scotland on July 5.PETER BYRNE/POOL/AFP via Getty Images

Queen Camilla, Britain’s King Charles III, Britain’s Prince William, Prince of Wales, and Britain’s Catherine, Princess of Wales, attend a National Service of Thanksgiving and Dedication inside St Giles' Cathedral

PETER BYRNE/POOL/AFP via Getty Images

Other couples in the royal family are more casual about public gestures of affection.

Last summer,Meghan MarkleandPrince Harryleaned in for asweet kissat the Santa Barbara Polo & Racquet Club in California where Harry was playing. The Duchess of Sussex tenderly held her husband’s face during the embrace, and the affectionate gesture called back tothe loving kiss they sharedafter Harry won the Sentebale Polo Cup in 2018.

Prince Harry and Meghan Markle at the Sentebale Polo Cup in 2018.Chris Jackson/Getty Images

Sentebale Polo 2018

Likewise, Prince William and Prince Harry’s first cousinZara Tindalland her husbandMike Tindalldon’t shy from showing affection at social sports events. Cameras caught acute momentbetween the couple at the Royal Ascot in June, where Mike gently helped his wife remove something from her eye as they rode in a landau carriage in the Royal Procession parade.

On the larger topic of PDA, Meier previously told PEOPLE that regular couples can take some cues from their favorite royals.

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“1. PDA such as a hand on the back or hand-holding shows care and comfort and is a safe bet,” she explained. “2. When in a professional role, practice professional behavior. 3. If you ever are engaging in PDA that may make someone uncomfortable, it’s best to take it to private quarters. An occasional sweet Sussex peck is one thing; a salacious snog is another!”

source: people.com