THE Queen revealed the King is "getting better” before adding jokingly "well, he would be if he behaved himself".
Camilla, 76, made the remark while with guests at a garden party in Rye, East Sussex where she was treated to a performance by actors Timothy West, 89, and Hayley Mills, 78, while sat alongside Prunella Scales, 91.
She added that her husband, the King, was “quite cross” he could not be there.
The King has recently returned to public duties following his cancer diagnosis after demanding aides "supercharge" his diary saying he was "raring to go".
The Sun has also previously revealed Camilla had urged Charles to "slow down" amid his health scares this year.
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Earlier, the book fan Queen revealed she dreams of being a student at Hogwarts, as she helped open a literary festival.
She also delivered an address and took a question from a local school pupil at the opening of the 35th annual Charleston, in East Sussex.
Children's laureate Joseph Coelho, Jacqueline Wilson, author of Tracy Beaker, actress Jenny Agutter, and Francesca Simon of Horrid Henry books took to the stage in front of 450 children to speak about their favourite children's books.
They were joined by comic Sir Lenny Henry who read a passage from The Cat in the Hat by Dr Seuss.
Local schoolgirl Bess, nine, asked the Queen: "Are there any fictional places from a book that you would like to travel to and why?"
Camilla joked: "One place I won't be going to is The Cat in The Hat."
Then added: "One place I think I'd love to go is Hogwarts. I'd like to jump on the Express and I'd like to go to Hogwarts and sit in that wonderful hall and wait for the hat to come round and pick a house for me.
"I'd like to look at Dumbledore, and Hagrid, and Snape, and see all the pictures going mad and people jumping out of pictures and the food flying about, I think it would be a proper magical experience, and that's a place I'd really like to go to."
Before the authors took to the to speak about their favorite books during the session called ‘Power of Reading’, the Queen delivered an address to around 450 children attending.
Prince William, 41, used a speech at The Royal Society in central London to call for action on antimicrobial resistance ‘for the sake of the generations that will follow’.
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The Prince of Wales is hoping to use his ‘global convening power’ to raise awareness of the deadly health issue - which kills an estimated 5 million a year.
Palace aides say antimicrobial resistance (AMR) - when bugs become immune to lifesaving antibiotic medicine - is a key issue for Prince William following his time as an air ambulance pilot, when he saw firsthand the importance of antibiotics.
In his speech, Wills spoke about the 'indiscriminate' threat of AMR.
He said: "Unless we act now and together, the ripple effects of drug resistance will be felt across generations, jeopardising the wellbeing of our children and our grandchildren.
"I am, however, hopeful. Thanks to the efforts and expertise of a great number of people - including many in this room - we now better understand the scale of the AMR threat."
The King and Queen will be joined by The Duke and Duchess of Gloucester at RHS Chelsea Flower Show on Monday, the palace has announced.
