Charles' speech also had a meaningful connection to the royal family. Both he and his daughter-in-law, Kate Middleton, went through their own cancer journeys after receiving diagnoses at the start of the year.

"From a personal point of view, I offer special, heartfelt thanks to the selfless doctors and nurses who, this year, have supported me and other members of my family through the uncertainties and anxieties of illness, and have helped provide the strength, care and comfort we have needed," he said. "I am deeply grateful, too, to all those who have offered us their own kind words of sympathy and encouragement."

Buckingham Palace confirmed in February that Charles had been diagnosed with an unspecified cancer and would undergo treatment, which he is reportedly still receiving. The Palace recently told NBC News that his treatment will "continue into next year" and that he is "moving in a positive direction."

The following month, Middleton shared her own surprise diagnosis after a planned abdominal surgery during which her condition was suspected as being non-cancerous resulted in tests indicating that cancer had been present. The Princess of Wales stepped away from royal duties as she underwent preventative chemotherapy and has recently been returning to the public eye following the completion of her treatment in September.