The marriage of Kate Middleton to Prince William in 2011 was a grand affair and a first for the royal family, with William choosing a bride from outside of royalty or aristocracy.
Now, a new book has made a surprising revelation about the conditions surrounding the couple's marriage. In Gilded Youth: An Intimate History of Growing Up in the Royal Family, author Tom Quinn claims that William and Kate's royal marriage was likely allowed due to the "usual precautions" being taken beforehand.
WATCH: A look back at William and Kate's royal wedding
Tom writes of the aforementioned precautions: "These are always carried out to ensure a future queen is able to have children. If Kate had not been fertile, there is little doubt the marriage would have been off."
The author refers to the marriage of the then Prince Charles and Lady Diana Spencer, suggesting that Diana underwent the same medical tests before her wedding to Charles in 1981.
Princess Kate in her beautiful bridal gown at her wedding to Prince William
He explains: "Diana complained in a brief encounter with the present author that she had in all innocence thought her premarital check-ups had to do with general health, only realising later on that she had actually been tested for fertility. 'I was so innocent I just went along with everything at that stage,' she said."
The author suggests that Princess Kate "must have known precisely what was going on, but she is not, nor has she ever been a rebel."
It's incredible to think that if these claims are true and if Kate had been found to have fertility problems, she may not have married Prince William.
Kate and William and a young George and Charlotte
William and Kate's wedding is still referred to as the royal wedding of the century.
Kate looked breathtaking in her stunning Alexander McQueen bridal gown, which featured long, lace sleeves, a beautiful V-neckline with sweetheart bodice underneath and a full skirt. It was a special moment as she entered Westminster Abbey on the red carpet and walked down the aisle to her future husband.
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Kate and William with their three children
Now, almost 12 years on, the royal couple are next in line to throne and have three lovely children, Prince George, Princess Charlotte and Prince Louis, with many royal fans wondering if they will have a fourth baby.
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