Princess Diana may not name Prince Charles by first name

• Princess Diana may only address Prince Charles as ‘sir’ until they are engaged.
• The princess was not supposed to call him by his first name, writes royal biographer Andrew Morton.
• “In Prince Charles’ circle, this is considered the norm,” Morton added.
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It is forty years since Prince Charles and Lady Diana Spencer announced their engagement on February 24, 1981.

The couple’s engagement interview has been watched worldwide by royal fans, but some people may not yet know how formal the couple was up to that point.

According to Princess Diana’s biography, “Diana: Her True Story”, by Andrew Morton, she had to call Charles ‘sir’ when they went out and she was only allowed to address him by his first name when they became engaged.

‘Only when Lady Diana was formally engaged to His Royal Highness, the Prince of Wales, did she get permission to call him’ Charles’. Until then, she had undoubtedly referred to him as’ Sir ‘,’ Morton writes in the book, first published in 1992.

While Diana also had an official title – she was formally known as Lady Diana until she was married – Charles used her first name.

“He called her Diana,” Morton added. “In the circle of Prince Charles it is considered the norm.”

Morton further explained that Diana’s older sister, Lady Sarah, was just ‘so formal’ during her nine-month relationship with the prince.

“It was right to do that, of course, because I was never corrected,” Lady Sarah told Morton.

Diana met Charles when she was 16 and the prince was 29. However, they only started a romantic relationship three years later. The couple met a total of 13 times before they got married, the princess later secretly recorded tapes for her biography.

In the same volumes, Diana famously calls her royal wedding the ‘worst day of my life’.

“I do not think I was happy. I never tried to turn it off in the sense that I really do, but I think [it was] the worst day of my life, ‘she said.

She also described herself as a lamb to slaughter. ‘

Footage of the tapes was first published in the 2017 National Geographic documentary, “Diana: In Her Own Words.”