She said: “When the late Queen died, William spoke of how she had been at his side at ‘the happiest moments’ and ‘saddest days of his life’.

“Now, Camilla is sharing some of those times with him and it must surely cement their relationship. There are so very few people that a senior royal can trust absolutely… and Camilla must now be one of that number for William.

“And I’m sure it is a two-way street with William offering moral support to Camilla as well.”

The Prince of Wales and the Queen have not always had the best of relationships, following the breakdown of King Charles’s first marriage to Willian’s mother, the late Princess Diana.

Ms Bond explained: “As an adolescent, William took his time to accept Camilla as ‘the other woman’ in his father’s life.

“His feelings towards her were complicated, having witnessed his mother’s unhappiness in marriage. But maturity brought with it the realisation that Camilla makes his father extremely happy… and the Prince knows now that she is the love of his life.”