Meghan Markle beams as she spends her birthday with Prince Harry at a friend's wedding

Meghan Markle is having a very happy birthday.

The former Suits star celebrated her 37th birthday on Saturday surrounded by friends -- at another couple's wedding. Markle couldn't have smiled brighter as she and her husband, Prince Harry, were photographed attending the ceremony for one of Harry's oldest family friends, Charlie van Straubenzee, 30, who tied the knot with Daisey Jenks, 27, in Surrey, England.

The Duchess of Sussex looked stylish at ever for the occasion, wearing a pleated shirtdress featuring an olive, pink and white skirt. She accessorized with a Philip Treacy fascinator, a knotted belt, black Aquazzura pumps and a clutch by Kayu. And unlike some of her more recent buttoned-up looks, Meghan opted to show a little skin, revealing a hint of black lace under her dress.

The actress had fun mingling with the other guests while Harry tended to his usher duties.

Also in attendance at the wedding were Harry's cousin, Princess Eugenie, and her fiance, Jack Brooksbank. The couple are set to marry at St. George's Chapel -- where Harry and Meghan said "I do" in May -- at Windsor Castle on Oct. 12.

A source recently told ET, meanwhile, that Meghan was surrounding herself with the support of Harry and a few other loyal friends as her father, Thomas Markle, continues to speak out about her to the press.

According to the source, Meghan and Harry have been hosting friends at their cottage in Kensington Palace, including Serena Williams and Meghan's best friend and stylist, Jessica Mulroney.

“Meghan doesn’t have a huge circle of friends and the recent weekends with Serena and Jessica were just what she needed,” the source says. “The stress of her father’s continued indiscretion is upsetting but she’s coping with it the best way she knows how with the support of her husband and BFFs.”

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