LONDON, ENGLAND - MARCH 6: Prince Charles, Prince of Wales reacts as he meets Matron Darlene Romaro (2R) and volunteer Diana Mukuma (R) and her dog 'Little Doris' during his visit to St. Thomas's Hospital on March 6, 2017 in London, England. The Prince, in his role as Patron of the British Geriatrics Society (BGS), met with doctors, nurses and healthcare workers to mark the Society's 70th anniversary at St Thomas's. (Photo by Chris J Ratcliffe - WPA Pool/Getty Images)