King Charles looked teary-eyed during his coronation ceremony, when his son, Prince William, joined in proceedings.
After King Charles was crowned, Prince William approached his father, kneeling before the King, reciting: "I, William, Prince of Wales, pledge my loyalty to you and faith and truth I will bear unto you, as your liege man of life and limb. So help me God."
He then bent down to kiss his father, with King Charles appearing overcome with emotion.
In a break with tradition, the Prince of Wales was the only blood prince to pay homage during the service, with his brother, Prince Harry sitting in the third row to witness the historical moment.
Prince Harry's initial reaction to the arrival of his family was caught on camera as he smiled and greeted attendees inside the Abbey before taking his seat.
However, following the revelations about the royal family in his book Spare and his Netflix documentary Harry & Meghan, fans were closely monitoring his reaction when he first caught sight of his older brother Prince William and his father King Charles.
Watch the moment the cameras panned to his face as his family members arrived for the coronation, including the Prince and Princess of Wales' children Prince George, Princess Charlotte and Prince Louis.
The Duke, who does not have any formal role in the coronation, looked dapper in a suit for the service instead of a traditional military uniform.
Prince Harry also interacted with his aunt, Princess Anne during the ceremony, looking delighted to see her as she entered the ceremony.
As the Princess Royal made her way through the abbey, she stopped to say hello to the Duke of Sussex, smiling animatedly at him, with Harry responding with a wide smile.
Prince Harry was seated closest to the aisle, with Princess Eugenie's husband Jack Brooksbank seated next to him, beside Princess Eugenie, followed by Edoardo Mapelli Mozzi, Princess Beatrice and Prince Andrew.
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The royal was decked out in a smart morning suit, complete with his medals, while Princess Anne donned full military regalia.
Before stepping down from his role as a working royal, Prince Harry wore uniforms to mark his former positions as Captain General of the Royal Marines, Honorary Air Force Commandant of the Royal Air Force Base Honington, and honorary Commodore-in-Chief of the Royal Navy’s Small Ships and Diving Operations.
Because he is no longer a working member of the royal family, he is no longer able to wear his uniform for royal occasions.
Princess Anne on the other hand, wore her Blues and Royals uniform with the dark green Thistle Mantle, and the Thistle Collar, Garter Sash, Garter Star, Thistle Star, GCVO Star, full sized medals, KCVO Star and Companion of the Order of the Bath neck decoration.