Beatrice and her husband Edoardo Mapelli Mozzi watched The Rolling Stones headline BST at Hyde Park in London on Sunday.
The royal smiled and looked relaxed at the music event over the weekend.
Beatrice’s appearance came after fresh claims emerged about the Duke of York’s Newsnight interview on his friendship with the late Jeffrey Epstein.
Producer Sam McAlister, who secured the bombshell interview for the BBC, said Beatrice joined her father at a meeting persuading him to appear on TV.
Ms McAlister, who has written new book Scoops, said Andrew’s eldest daughter was “evidently anxious” and “clearly there to protect his interests”.
She added that she believed Beatrice was “the person who could make the difference between us getting the interview or not”.
Writing in her new book Scoops, Ms McAlister said: “To be frank, the only thing worse than speaking to a prospective interviewee about allegations of sexual impropriety and sex with a 17-year-old girl is having to do so in front of his daughter.
“Princess Beatrice was polite and engaged, but, unlike her father, she was evidently anxious about the meeting and clearly there to protect his interests.
“I’d heard she was close to the Queen.
“The Prince’s eldest daughter was now, I felt, the person who could make the difference between us getting the interview or not.”
Andrew has always denied the allegations against him.
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