Pictures of Princess Diana and Sarah Ferguson

In addition to becoming Royals in the 1980s, Princess Diana and Sarah Ferguson were distant cousins—both descendants of the fourth Duke of Devonshire, William Cavendish. However, they formed a relationship mainly due to the fact that their mothers attended the same school. They lived together during their childhood and, though they separated for a time, they reunited in the 1980s before both became members of the Royal Family.

Sarah, 21, and Diana, 19, met again through mutual friends and soon became inseparable, even seeing each other every week to dine and hang out. During that time, Diana was already dating Prince Charles and just a year later she would marry in one of the most iconic royal ceremonies of the modern era.

Diana's marriage to Prince Charles is known to have been fraught with tension and trouble even before it took place. During this difficult time, Sarah became something of a confidante. Ferguson mentioned in her 1996 autobiography, writing, "She was two years younger than I, and I strove to support and protect her as I would a younger sister—as I still do today, as a best friend."

Diana invited Sarah to her wedding ceremony, but she was not present at the private party that preceded it. It wasn't until four years later that Diana was able to invite Ferguson to one of the 1985 Royal Ascot events where Sarah and Prince Andrew connected. They already knew each other but it was not until this moment that they really fell one another.

For Diana this relationship became a respite and a distraction, so she constantly organized meals and events for the couple to meet and continue their romance. In other words, Diana really enjoyed playing cupid with her friend and brother-in-law.

When her relationship with Prince Andrew became official, Sarah began to experience the stress and anxiety that Diana had told her about. So, it was at that moment that Diana became her guide in dealing with the attention, the media, and the strict protocols of the Royal Family.

Sarah's insertion into the Royal Family was truly a respite for Diana who looked happier and even more amused in the public eye. In fact, it was common to see them laugh or fool around during public events, something that was approved of by neither the Royal Family nor the conservative media of the day. They argued that, as partners of the heirs to the Crown, Diana and Sarah should behave with total solemnity.

Soon, the media did not hesitate to compare them. And, despite their closeness, Diana and Sarah were both very young and ended up giving in to rumours and comments. For example, it was very difficult for Diana to see how Sarah had gained the admiration of Queen Elizabeth and Prince Philip so quickly, something that she did not believe she had achieved over the years. What's more, as Diana herself stated, even Prince Charles told her that she should be more like Fergie.

However, Fergie's popularity would not last forever: After her separation from Prince Andrew, she even became a problem for the Royal Family. During the early '90s, their lives caused quite a controversy, but they stuck together... for a while.

The publication of Sarah Ferguson's autobiography in 1996 ended up revealing the distance between them. As Ferguson commented years later, Diana simply turned away from her and stopped talking to her without giving any explanation. It's believed that the main reason was that she was not consulted about what was said about her in the book and, clearly, that there were private things that Ferguson should not have published. Tragically, the Princess of Wales died the next year in a car crash at age 36.

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