Princess Diana and Sarah Ferguson.Photo: Tim Graham/Getty Images

Sarah, whose title is Duchess of York (and who is popularly known as Fergie), appeared onThe Kelly Clarkson Showfollowing the release of hernew novel,A Most Intriguing Lady. She had both the host and actor Ike Barinholtz cracking up as she recalled her eventful hen party, the British equivalent of a bachelorette party, ahead of her1986 royal weddingto Prince Andrew.
Ferguson, 63, said she and Princess Diana were dressed up in cop costumes for a night out at a club — and a photo showed the pair sporting uniforms with matching caps (and Diana in a pair of black frame glasses) with drinks on the table in front of them.
“We sat down, and the waiter came up to us and said, ‘Excuse me, this is a members club. And it’s for fun, and we don’t serve police officers here,’ " she explained.
“They thought you were real police officers?” Clarkson asked, to which Sarah replied, “Yes!”
Princess Diana and Sarah Ferguson.The Kelly Clarkson Show

When they left the club, Princess Diana broke character when she saw a woman wearing a dress she had. Then, the pair were arrested for “impersonating police officers” and even put in the back of a police van. But when Princess Diana noticed “smoky bacon flavored crisps” in the van, she “started taking them and eating them.”
Sarah said, “The policeman in the front seat — ‘You can’t do that!’ "
Although the women turned their engagement rings from view in the police van, the cops eventually realized who they were.
Fergie said that she doesn’t miss Princess Diana, who died in a 1997 car crash, because “she’s with me all day.”
“She and I, we laughed a lot. We got into trouble a lot,” Ferguson continued. “You know what she used to do? She used to tell me the worst story, joke story, just before I had to be serious.”
The Duchess previously told PEOPLE that she and Princess Diana, whom she affectionately called “Duch,” werebest friends from the time they were teenagers, long before Diana married the then-Prince Charlesand Sarah married his brother Prince Andrew. She recently said that Princess Diana would be"incredibly proud” of her five grandchildrenfrom her sons,Prince WilliamandPrince Harry.
Sarah, who is agrandmother herselftoPrincess BeatriceandPrincess Eugenie’s children, said during a recent appearance onGood Morning Americaof Diana, “I think we’d have a ‘Granny-Off.’ Because she would run faster in the races. I wonder — she’d probably be funnier. No, I think I’d be funnier.”
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Sarah Ferguson and Princess Diana in 1983.Georges De Keerie/Getty

Becoming a grandmother came naturally to the longtime children’s book author, whose bestsellingBudgie the Little Helicopter series became a popular animated show and whose enduringLittle Redcharacter also inspired a series of books. The Duchess also hosts a YouTube series for children,Storytime with Fergie and Friends.
“Everyone says, ‘Oh, has it changed your life?’ And I go, ‘No because I live [in the mindset of ] 3- to 6-year-olds.’ So I’ve now got another audience that likes me,” shetold PEOPLE.
source: people.com