Also attending are Prince Charles and Camilla, Prince Harry and Meghan, the Duchess of Cambridge's parents, her brother and sister and Louis's six godparents, who are close friends or relatives of William and Kate.
This, her first military post as a member of the Royal Family, was given to her in December 2015 upon Prince Philip relinquishing the position and passing it over to her.
The christening was not the first time the princess has unleashed her sass.
Meghan Markle's latest royal appearance provided more proof of how well she's getting along with her royal in-laws. Kate Middleton went with an icy blue dress by her go-to designer, Alexander McQueen, and a hat by Sean Barrett.
She also took the Royal Salute at the ceremony as her relatives including the Prince of Wales and the Duchess of Cornwall, the Duke of Cambridge plus the Duke and Duchess of Sussex watched nearby.
Several Yahoo commenters noted a strong family resemblance: "Man oh man, these pictures show how much Princess Charlotte looks like her daddy!" one reader said.
The three-year-old was walking hand-in-hand with her dad Prince William after the service at the Royal Chapel at St James's Palace told waiting photographers: "You're not coming".
Nicholas Van Cutsem, Harry Aubrey-Fletcher, and Guy Pelly are Prince Louis' godfathers.
Critics noticed right away that Kate Middleton looked less than pleased to be standing so far away from Queen Elizabeth and the rest of the royals. The duchess wore a Ralph Lauren dress, a Stephen Jones hat, Manolo Blahnik shoes, as well as gloves and a clutch. Kate actually re-wore that same cream coat at the wedding of Prince Harry and Meghan Markle in May 2018.
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