'That was good news from where I was sitting and Sarah seemed delighted I was so keen to share it with the nation,' Whitaker said.
Following the end of their relationship, Charles sparked up a romance with Sarah's younger sister - the late Lady Diana Spencer.
However, despite their history Sarah not only gave Charles and Diana her blessing, she also set them up on their first date, telling The Guardian in a later interview: 'I set them up, I'm cupid.'
Four years later in 1981, Diana became the Princess of Wales after tying the knot with the royal in a world-famous ceremony while Lady Sarah wed Neil McCorquodale.
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