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The Queen Mother thought Prince Charles was "very sensitive" and that his marriage to Princess Diana was a "terrible mistake", according to a friend of the late princess.
Petronella Wyatt said the Queen Mother, who died in 2002, treated Charles like the son she never had and thought he was desperately sad when he was married to Diana.
Charles and Diana married in 1981, when he was 30 and she was 19. There were strains within a few years and they were separated by 1992, and divorced in 1996.
Wyatt, a friend of the late princess, told The Sun of how the Queen Mother used to dine with her parents, Woodrow Wyatt and Veronica "Verushka" Banszky von Ambroz.
She said: "Her desperation over the Charles and Diana situation had unnerved her. Charles was her darling, the son she never had. Naturally, she felt wretched when Charles and Diana became antagonists, brawling like longshoremen.
"'My grandson is so desperately sad,' she would say, her eyes almost welling up."
Wyatt said of the Queen Mother and the heir to the throne: "The Queen Mother adored Charles. She once described him to me as 'very sensitive'. But he was spoiled and used to getting his own way.
"He needed careful managing, unconditional love and someone to jolly him along in an almost motherly way. Very few people could have done it. Diana was too green and even more sensitive than he."
Wyatt said the Queen Mother had told her father the marriage of Charles and Diana was a mistake.
Charles had been in a brief relationship with Camilla Shand in the 1970s, but it's said he was discouraged from marrying her, and she went on to marry Andrew Parker-Bowles.
The prince met Lady Diana Spencer around the time he was dating her sister, and the two eventually became starting a relationship.
But the marriage was a difficult one, and Charles admitted that he had an affair with Camilla when his union with Diana was broken "irretrievably".
Diana went onto give an explosive interview with Panorama and told Martin Bashir "there were three people" in her marriage, referring to Camilla.
The interview led to the eventual divorce of the couple, with Diana losing her royal security and her HRH titles.
However, Wyatt also recalls that the pair had managed to become friends after their separation, even suggesting Charles had grown to love her.
A recent report by Lord Dyson found Bashir had used "devious and deceitful" methods to secure the 1995 interview.
Princes William and Harry criticised the methods used by Bashir and the BBC in statements given in response to the report with William saying his mother was let down.
Diana would have turned 60 on 1 July, and William and Harry will unveil a statue of her in the Sunken Garden of Kensington Palace on that day.
As well as journalism, Wyatt is known for having an affair with Boris Johnson between 2000 and 2004.
Johnson was an MP at the time and was sacked from a shadow cabinet position for lying about the affair when details emerged.
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