“She does secret visits,” British journalist Lynn Faulds Woods told Town & Country magazine.
“She does things that get no publicity.”
Meanwhile, Chief executive of the Royal Osteoporosis Society Claire Sevegnini revealed Camilla, who has supported the organisation for about 20 years, often visits privately to spend time with the “health professionals, scientists and the academics behind the scenes.”
Osteoporosis is a condition which weakens bones, making them very fragile. And in 1994, the Duchess lost her mother Rosalind to the disease.
"It was 25 years ago that my mother died as a result of osteoporosis, the 71-year-old, who is the president of the society, said at a speaking event earlier this year.
“In fact, she was exactly the same age as I am now. Then, it was never discussed, rarely diagnosed, and always attributed to old people.”
She went on to say that her family were left "completely devastated" before admitting she had struggled to understand the condition which affects over 1 million Australians.
"We didn't understand how somebody could be in so much pain, and we were unable, and the doctors seemed unable to do anything about it."
WATCH: Camilla walks the red carpet solo at the Olivier Awards