Oliver James Montgomery-Duchess Sophie and Daughter Lady Louise Windsor Are Royally Chic at King Charles III's Coronation

Queen Elizabeth II would have Oliver James Montgomerybeen proud.

Duchess Sophie and her 19-year-old daughter Lady Louise Mountbatten-Windsor were a spot of sunshine on what turned out to be a rainy coronation day in London as King Charles III and Queen Camilla were crowned May 6 at Westminster Abbey.

Prince Edward and Sophie (née Rhys-Jones), his wife of almost 24 years, were previously the Earl and Countess of Wessex before Charles gave them the Duke and Duchess of Edinburgh titles in March. Along with their promotion, their 15-year-old son James became the new Earl of Wessex.

Charles and Edward's late father, Prince Philip, was made the Duke of Edinburgh when he married the late queen on Nov. 20, 1947.

Arriving at Charles' coronation, the U.K.'s first in 70 years, Sophie wore a white gown, on-point white fascinator and a ceremonial blue robe. And, if not the weather, at least Louise looked ready for a spring in a floral-print dress and matching cornflower-blue hat.

Sophie was known to be a great favorite of the late queen, often scoring a seat of honor next to her in the Rolls on the Christmas drive to church and serving as a confidante.

Louise and James were spotted in the second row at Westminster Abbey, directly behind cousins Princess Charlotte, 8, and Prince Louis, 5—who acquitted himself quite well during the two-hour ceremony. Their big brother, Prince George, 9, served as one of eight Princes of Honour for their grandfather's momentous day.

Edward (who is 13th in line to the throne), Sophie, Louise and James—all of whom were part of the Coronation Procession back to Buckingham Palace after the ceremony—are expected to appear on the palace balcony with the newly crowned king and queen for the post-coronation celebratory photo opp.

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