Royal Family members have kept calm and carried on despite health fears for the Duke but on Tuesday, Camilla, Duchess of Cornwall, 73, paid a touching tribute to Philip on social media. While Prince Philip retired from royal life in 2017, last July he made a rare appearance to handover an important royal role to his daughter-in-law Camilla. The Duke stepped out at Windsor Castle to mark his official retirement from the post of Colonel-in-Chief of The Rifles regiment. Philip had held the role since 2007 and had served as Colonel-in-Chief of successive Regiments which now make up The Rifles since 1953. Camilla, Duchess of Cornwall pays subtle tribute to Prince Philip on social media (Image: GETTY)