Queen Camilla and King Charles have supported one another since taking to the throne. At joint engagements, the King and Queen are always all smiles together as they carry out their royal roles. However, while the couple are as solid as can be, it seems that the Queen, 77, has been frustrated at King Charles over the last year for one thing.

On multiple occasions since the King first announced his cancer diagnosis last year, Camilla has expressed frustration at her husband’s lack of ability to rest and follow doctor’s orders. Despite missing some engagements, the King, 77, has seemed as determined as ever to carry out royal duties while undergoing treatment.

While the Queen is supportive of Charles, her frustration at his inability to rest was made clear last year in a nine-word remark made to author Lee Child.

She said that despite urging Charles, 76, to take it easy, he “won’t slow down and won’t do what he’s told”.

The King himself appeared to be frustrated last year also when during a trip to Australia and Samoa he hinted that he was not pleased at the restrictions that had been put on him as a result of his cancer diagnosis.

Speaking at the Commonwealth Heads of Government Meeting (Chogm) in Samoa last year during the tour, the King said: “It remains a lifelong aspiration to have visited all the countries of the Commonwealth – although nowadays it seems to be a race against our happily increasing numbers – as well as doctor’s orders.”

Despite this, the monarch still managed to complete the jam-packed autumn tour, which saw his schedule altered to ensure he also had time to rest.

The monarch is also set to complete overseas tours this year with Queen Camilla, with the couple set to fly to Italy together next month for various royal engagements if the King is given the go-ahead by doctors.