LONDON, ENGLAND - JULY 09: Princess Charlotte and Prince George hold the hands of their father, Prince William, Duke of Cambridge, as they arrive at the Chapel Royal, St James's Palace, London for the christening of their brother, Prince Louis, who is being carried by their mother, Catherine, Duchess of Cambridge on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 09:  Britain's Prince Charles, Prince of Wales (R) and Britain's Camilla, Duchess of Cornwall attend the christening of Prince Louis at the Chapel Royal, St James's Palace on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 09: The Duke and Duchess of Sussex depart after attending the christening of Prince Louis at the Chapel Royal, St James's Palace on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 09: Catherine Duchess of Cambridge and Prince William, Duke of Cambridge with their children Prince George, Princess Charlotte and Prince Louis after Prince Louis' christening at St James's Palace on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 09: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge with their children Prince George, Princess Charlotte and Prince Louis after Prince Louis' christening at the Chapel Royal, St James's Palace, London on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)