The Duchess of Sussex faces being quizzed in court over intimate details revealed in a tell-all biography after the authors admitted that she was a source.
Finding Freedom, published yesterday, lays bare the innermost thoughts of the Duke and Duchess and the tensions behind the scenes that led up to their departure from official royal life.
It includes the claim that the Prince of Wales' 70th birthday photograph, which seems to show a happy picture of family unity, was an "absolute nightmare" to plan because his sons blew "hot and cold" with their father.
The 350-page book is expected to be thrust to the heart of a High Court privacy case brought by the Duchess against The Mail on Sunday.
The Sussexes have distanced themselves from the book, while Omid Scobie and Carolyn Durand, its authors, have repeatedly insisted the pair were not interviewed and did not contribute, despite a startling level of detail of their innermost thoughts and feelings.