She said: “I am proud to bring my personal brand of historical fiction to the publishing world.”
Outside of the formal, high-brow world of literature, the Duchess is known to enjoy letting her hair down.
She was the first royal to have ever had a “proper hen party or bachelorette party”, according to royal commentator, Ayesha Hazarika.
Fegie is also lucky enough to have Jack Brooksbank as a son-in-law.
Ms Hazarika said: “Diana was invited, and they had a lot of fun, they dressed as policewomen and they caused a bit of a scene at the Palace.”
Further details of the night were revealed in the Duchess’ autobiography following her divorce from Prince Andrew in 1996.
Lizzie Cundy, a friend of Fergie’s, said the evening had degenerated as the Duchess and Princess Diana continued to celebrate around London.
Ms Cundy said: “These two apparently got put into a police van where the policemen recognised Diana and said, ‘Oh, my goodness, I’m so sorry.’
“And they all fell in fits of laughter.”
Reports at the time suggested the pair had donned fake police uniforms to crash Fergie’s then-fiance Andrew’s stag do celebrations and reunite with their respective partners.
But a last-minute change of plan saw them go to London nightclub Annabel’s, where they were mistaken for kiss-o-grams – girls paid to dress up as characters and attend parties to kiss people.
The manager of the club, Lewis Louis, said customers had originally thought it was a police raid but then concluded the two women in fancy costumes were kiss-o-grams.
Mr Louis said: “One of the staff told them that one or even two ‘kiss-o-gram’ girls might be alright but four of them was a bit of an embarrassment to others.”
Sarah’s ‘Her Heart for a Compass’ is due to be published by Mills & Boon on August 3, 2021.