The former Olympic swimmer, 47, cut a glamorous figure in a red blouse and matching trousers as she joined Prince Albert, 67, at the annual occasion in Monte Carlo over the weekend.
The delegation of European royals have arrived in St Peter's Square for the funeral of Pope Francis, with Prince William representing his father King Charles at the ceremony.
The royal mother-of-two, 46, arrived at the former French minster's funeral at Monaco's Notre-Dame-Immaculee Cathedral alongside her husband, Prince Albert of Monaco, 66.