“He is a man with a keen sense of curiosity and I’m sure he will be hoping on his birthday that the visit to Australia and Samoa marked a turning point in his recovery and that he will indeed be carrying out almost a full diary of engagements in the coming year,” she says. “I think he has found it very tough to heed the advice of his doctors, along with his wife and his friends, to slow down a bit.”

Of course, easing his workload will become necessary going forward, with Jennie adding: “There is no getting away from the fact that we now have a fairly elderly King and Queen. Camilla’s recent chest infection is a reminder that neither of them is a spring chicken and they cannot be expected to go full pelt into the coming year. Charles will undoubtedly have much to reflect on as he celebrates his 76th birthday.

“He can be a very introspective man and some people feared that his cancer diagnosis would make him morose. But by all accounts he has been positive from the start, he has used his own illness to encourage other men to come forward for tests.

“I think he appreciates that suffering from cancer has made him somehow more relatable… and the mountains of letters and cards wishing him well have made him understand that he really does hold a place in the heart of many, many people.”
And looking ahead to the coming year, the King has a great deal to look forward to, including two major tours after his recent overseas visit proved to be “the perfect tonic”, as well as his and Queen Camilla ’s 20th wedding anniversary on 9 April.

While King Charles simply wouldn’t be the man he is today without the steadfast example set by his late mother, the role his “darling wife” Camilla plays cannot be understated.

She is not only his spouse, but his sounding board and his best friend as Jennie says warmly, “I always think of them as a pair of old, comfy slippers – completely content in one another’s company, and rather lost when one of them is absent.”