Meghan Markle Goes Floral & Coordinates with Prince Harry at Wedding of Princess Diana's Niece

Just one month after Meghan Markle and Prince Harry said “I do,” the royal couple were all smiles as they attended the wedding of Princess Diana’s niece.

Celia McCorquodale, who is the daughter of Diana’s eldest sister Lady Sarah McCorquodale, walked down the aisle on Saturday as she tied the knot with George Woodhouse at St. Andrew and St. Mary’s Church in Stoke Rochford, Lincolnshire.

To celebrate the happy occasion, Meghan, 36, wore a long-sleeve blue-and-white floral print Oscar de La Renta dress, which retails for $5,490. While she opted out of wearing pantyhose for her latest royal outing, she did accessorize her fashionable dress with a white fascinator and a pair of matching high heel shoes.

Adding a touch of color to his distinguished three-piece suit, Harry, 33, opted for a blue tie, which coordinated perfectly with his wife’s dress.

As the couple made their way into the church, the newlyweds walked hand-in-hand in a sweet nod to their own matrimonial bliss.

Both Meghan and Harry was also spotted sharing a friendly greeting with Harry’s cousin Louis Spencer — who is the son of Diana’s brother Earl Spencer.

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Louis was present at the couple’s nuptials last month, and made quite a splash once people realized just how handsome (and available) he is.

Louis inherited some of his good looks from his mother’s side of the family, as his mom Victoria was a model prior to marrying Louis’ father in 1989 — eight years after Harry’s parents tied the knot.

During the ceremony, Celia included a stunning tribute to the late Diana in her wedding look by wearing the Spencer Tiara, which Diana wore in 1981 when she married Prince Charles.

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Lady Kitty Spencer, Diana’s niece and brother to Louis, was also on hand for the day, opting to wear a belted floral print dress with a red veiled fascinator and matching heels.

Joining the happy wedding party were Diana’s sisters, mother-of-the-bride Lady Sarah McCorquodale and Lady Jane Fellows, and her brother Charles, 9th Earl Spencer, and his wife Karen, the founder and CEO of Whole Child International.

This is Meghan’s first appearance since her one-on-one outing with Queen Elizabeth on Thursday.