Meghan Markle applauds Prince Harry at the polo match on Princess Diana's birthday

The The Duke and Duchess of Sussex attended the charity event Sunday, where the Duchess donned her pre-royal style, swaying a simple white button and black capri pants. She completed the outfit with a pair of black dishes and wore her hair in her signature rash look.

The two also attended the polo event on Saturday, where the Duchess was joined by a friend Serena Williams on Prince Harry and Prince William during their match at Coworth Park Polo Club. However, neither Kate nor William appeared at the event on Sunday.

The Audi Polo Challenge is not, however, a charity event for honeymooners. The case probably has significance in the heart of the royal couple. Last year, the couple made an appearance at the game – their first public appearance as a couple. The two also shared a kiss, which was taken on the camera for the spectators and royal fans to see.

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The couple, who has just been married a month, have barely had time to enjoy their newlywed happiness: Between them, they have already traveled and made appearances at several different events. Last month, Meghan took her first solo trip with the Queen, during which they stopped at a few locations around Chester, England.

But polo was probably not the only thing today: today would have been the 57th anniversary of the end of Princess Diana. The former princess died more than 20 years ago, in 1997, and Harry and William made it clear that they still kept his memory very close to them.