Meghan Markle joins Prince Harry for polo on Princess Diana's birthday

Meghan Markle and Prince Harry returned to the Audi Polo Challenge on what would have been the 57th birthday of Princess Diana

The Duke and Duchess of Sussex arrived together at the event annual charity. Meghan, 36, opted for a white casual shirt and a pair of fitted black capri pants, which she accessorized with a pair of black flats, sunglasses and what appears to be the same panama Madewell x Biltmore that she wore

Meanwhile, Harry was seen arriving in a white polo shirt with stripes on the side, which he paired with white pants and boots.

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Meghan also attended the event Saturday, while she was encouraging Harry and his brother Prince William while the Royal brothers went to the field at the Coworth Park Polo Club. William was not seen arriving at the event on Sunday.

The Audi Polo Challenge probably holds a special place in the heart of Meghan and Harry: Their appearance at the game last year was the first time the couple attended a public event together, and they marked the milestone with a kiss.

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Prince Harry

Mark Cuthbert / British Press via Getty Images

Also present was actor Eddie Redmayne, who attended Eton College in the early 2000s with William. In addition to playing in the same rugby team, they were also honored as members of the elite elite group responsible for exercising discipline at school.

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In a gentle wink to Diana, Meghan and Harry found many ways to honor his legacy at their wedding in May .

Diana's favorite flowers: Forget-Me-Nots.

The Duke and Duchess also included another of Diana's favorite flowers – white garden roses – in a unique floral show.

VIDEO: How Prince Harry and Meghan Markle have subtly honored Princess Diana in their wedding photos

Later in the day special, Meghan was seen wearing the aquamarine ring of Diana on her right hand while she and her husband were seen leaving for their wedding reception.

Diana famously wore the emerald cut Aquamarine stunner at an auction of her own clothes at Christie's in 1997.

Meghan Markle and Princess Diana

Steve Parsons – WPA Pool / Getty Images; Tim Graham / Getty Images

RELATED: In honor of the birthday of Princess Diana, we look back at some of her most memorable moments of style

In a last glance at Harry's mother, couple included a special detail in one of their wedding photos!

In an image released by the palace, while Meghan sits on the floor of Windsor Castle's green living room, Harry sits on an emerald green couch. It was the same sofa on which Harry's mother was photographed sitting holding a baby Harry at his baptism in 1984.

Prince Harry, Meghan Markle and their pages and bridesmaids pose in the green living room of Windsor Castle

Alexi Lubomirski / AP / REX / Shutterstock

Diana sits next to Queen Elizabeth while Prince Charles was resting on his arm antique furniture next to her. In the middle of the photo was a young William dressed in a white polo shirt and a baby blue shorts while he was smiling off camera.