The story of Princess Diana and Prince Charles is comparable to those stories written on the children's books which started with "once upon a time." The only difference is that it never ended with "and they lived happily ever after."

The grand wedding on July 29, 1981 became the most-awaited wedding at that time, with over 750 million spectators pausing their lives to witness Princess Diana and Prince Charles' exchange vows.

But who would have thought that the "Wedding of the Century" could turn into a heartbreak?

In Andrew Morton's book entitled "Diana: Her True Story", it was revealed that Prince Charles and Princess Diana were unhappy since there were "three people" involved in the marriage.

After giving birth to Prince Harry, Princess Diana revealed that it marked the beginning when her relationship with Prince Charles started to be on the rocks. Two years after Harry was born, Prince Charles reportedly restarted his romantic entanglement with Camilla.

Before the cheating reports came out, Princess Diana already knew about it and tried her best to save their dying marriage.

The Princess of Wales, out of her love for her sons Princes William and Harry, stood up bravely and confronted Camilla for the first time at her sister's birthday party.

Princess Diana waited for the perfect moment until Camilla was left alone then directly told her that she was aware of what was going on. However, Camilla just shrugged her off and told her she had no idea what she was talking about.

"I know what's going on between you and Charles, and I just want you to know that," Diana explained.

Camilla still tried to convince Princess Diana to let Prince Charles go since the Princess of Wales already had everything. But the princess stood firmly and told her that she only wanted Prince Charles.

However, Diana's efforts were put into waste when the royal couple decided to get a divorce in 1996.

What Princess Diana Saw On Their Wedding Day

On the busy streets of London, as she walked down the aisle at St. Paul's Cathedral, Princess Diana already saw the sign.

In the same biography book written by Morton, he stated that Princess Diana spotted Camilla, who became the cause of her failed marriage with Prince Charles.

"So walking down the aisle I spotted Camilla, pale grey, veiled pillbox hat, saw it all, her son Tom, standing on a chair. To this day you know - vivid memory," Diana said, as what the taped conversations for the novel recorded.

Diana saw the warning but still did everything in the hopes that Prince Charles might still change his mind. But her dream to have a complete family lasted only for a day, and it stopped there as she never had the chance to win the heart of Charles from Camilla.

The royal princess tragically passed away when she got into a car accident in Paris a year after their divorce. She was together with her then-partner Dodi Fayed and driver, Henri Paul.

If only she did not overlook the important hint she saw on their wedding day, would everything else be different? Would Prince Charles be able to marry Camilla?

Maybe the story of the two royals with Camilla in the middle is something made of unanswered questions and what-ifs. Too bad, it had to stay that way to give everyone the peace of mind they deserve.

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