Instead of supporting her husband, Princess Diana stood firm and refused to back Prince Charles as future King of the U.K. monarchy.

Prince Charles and Princess Diana indeed had an ugly marriage in the past. Even royal watchers witnessed how the Prince and Princess of Wales went from a happy marriage to an unexpected split.

Because of the disparaging moments she experienced with the heir to the throne, the People's Princess became sure that he would never be fit to reign the monarchy.

A former newspaper editor dropped some previously unknown revelations about the former royal couple through a new documentary.

On Wednesday, the "In Diana: The Truth Behind the Interview" debuted and dropped bombshell truths reportedly made by royal princess.

According to Max Hastings, the Princess of Wales met her three months before she revealed to the world the bad experiences she had during her marriage with Prince Charles.

To recall, Princess Diana made noise in 1995 after she disclosed the heir to the throne's infidelity.

Decades after the interview, Hastings divulged the things he heard from the princess herself, especially how much undeserving Prince Charles is to become king, per People.

Princess Diana Blocls Prince Charles

Per the editor, Diana suggested to let Prince William take over the throne instead.

"She said that all she cared about was William's succession to the throne. She said to me quite explicitly - 'I don't think Charles can do it,'" Hastings recalled.

He added that the princess wanted to witness how Prince Charles would give way and let their son take over the throne.

As to why he never disclosed this information, the former editor argued that he aimed to "keep a lid on the worst of this."

In addition, he saw most of Princess Diana's statements as something "for the fairies" only.

More Degrading Revelations About Prince Charles

This bombshell news came after Netflix announced that the next season of "The Crown" will arrive on the platform.

It will mainly tackle Prince Charles' cheating issues, from how he decided to marry Princess Diana until the time he fought for his love for Camilla, now Duchess of Cornwall.

In her 1995 Panorama interview, Princess Diana revealed that she was aware of the infidelity since the beginning.

"There were three of us in this marriage, so it was a bit crowded," she said that time. "But I wasn't in a position to do anything about it."

Meanwhile, when Hastings heard Princess Diana's story personally, he realized how much she hated Prince Charles.

The Princess of Wales hated it so much that she never had a single happy time. Instead, she saw the marriage as hell from the beginning.

Aside from Hastings, Andrew Morton also confirmed this statement in the book entitled "Diana: Her True Story."

Princess Diana told him that they were unhappy since there were "three people" involved in the marriage.

Prince Charles' infidelity was also mentioned in "Diana: Her True Story - In Her Own Words," saying that what the royal prince did make her miserable, and she wanted to speak it all out so the world would know her side and what she was going through.

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