Sarah Ferguson told People magazine she andPrincess Diana promised "they would always be together."- Ferguson and Diana met as teens - later they became sisters-in-law.
- Shutting down rumors of a feud, Fergie revealed the two used "have an incredible time together."
Sarah "Fergie" Ferguson denied rumors that she feuded with Princess Diana before her death in a new interview.
Speaking to People, the Duchess of York said she and Princess Diana met when they were just teenagers and "promised each other we would always be together."
"There was never any daylight between us," she told the outlet. "But everybody wanted that, because we were so strong together.
"People want to break something so strong," she added.
Ferguson also told the publication that they were "best friends" from the ages of 14 and 15.
When Ferguson married Prince Charles' younger brother, Prince Andrew, she and Diana became family. Nigel Cawthorne, author of Call Me Diana: The Princess of Wales in Her Own Words, told Insider: "It was Diana who saw that Sarah could be the one for Andrew. They both enjoy practical jokes and like a good time without being complicated or envious."
Marrying into royalty meant both Diana and Ferguson were both living in the public eye. "She taught me so much of public life," Ferguson said. "She was so brave. We used to have the most incredible time together."
Despite the fun, there has long been speculation that Diana and Ferguson's relationship was not always on the best of terms.
Cawthorne told Insider: "There probably was tension once Sarah was the Duchess of York and didn't have to rely on Diana as much as before. But when their marriages collapsed they both had a shoulder to cry on."
In an interview with Harper's Bazaar in 2007, Ferguson said she and Diana had not spoken in the year leading up to her death.
"I never knew the reason, except that once Diana got something in her head... I tried, wrote letters, thinking whatever happened didn't matter, let's sort it out," she told the publication. "And I knew she'd come back. In fact, the day before she died she rang a friend of mine and said, 'Where's that Red? I want to talk to her.'"
Ferguson also told People what she thought Diana would think about sons Prince William, 39, and Prince Harry, 36, today.
"If she were sitting with me right now, I know she would say, 'I am so proud of both of my boys and the wonderful wives they have chosen,'" Ferguson said. "Because each has got her own voice," she added, speaking of their wives Kate Middleton and Meghan Markle.
According to Ferguson, Diana would've also been "obsessed" with her grandchildren.
"That's what she loved," she said of Diana, who "adored" her daughters Princess Eugenie, 31, and Princess Beatrice, 32.
"She adored her boys. This would have been her haven. Her heaven," she added.