Prince Edward, Prince Charles, Sarah Ferguson and Princess Diana
Pictured: Prince Andrew, Sarah Ferguson, Lord Linley, Prince Edward, Prince Charles, Princess Diana, Queen Elizabeth II and Queen Mother outside Clarence House in London on Aug. 4, 1989. Getty Images/Johnny Eggitt

Prince Edward and Sarah Ferguson were once close friends, but their fondness for each other eventually turned sour.

In the 1993 book “Prince Edward,” royal biographer Ingrid Seward said that before Prince Edward and Fergie became notably detached, they actually got on very well with each other.

“She was not Edward’s romantic type – she is much too jolly-hockey-stick for his taste – but they certainly only established a friendly rapport. On occasion, Sarah would drive into Soho and join Prince Edward and theater director Biddy Hayward for lunch at a nearby bistro,” Seward said.

Eventually, Ferguson formed friendships with Steve Wyatt and John Bryan. She also developed extensive spending habits and started alienating herself. After this happened, Prince Edward also became distant from the Duchess of York.

The Royals felt that Prince Andrew’s wife stepped beyond the bounds of good behavior. And Queen Elizabeth’s former private secretary Lord Charteris summed up their attitude when he described her as vulgar.

“Fergie took the decision to break loose – and promptly found herself frozen out by the Palace machine. There were to be no more lunches with Prince Edward,” Seward said.

And during one incident, Prince Edward and Ferguson got into a heated row after he accused her of leaking details about his relationship with Sophie, Countess of Wessex to the press.

Several years ago, Ferguson would go to the palace with Princess Beatrice and Princess Eugenie so that her daughters could spend time with their grandmother. Ferguson didn’t stay with them because Prince Philip didn’t want her to be there.

But during one occasion, Prince Edward saw Ferguson talking to Sophie over lunch. As a result, the dad of two became suspicious of Ferguson and he also became convinced that she leaked his relationship with Sophie to the media.

Prince Edward and Sophie ended up tying the knot a few years later. As of late, it is still unclear if he has made up with Ferguson.