South African fitness coach Jenni Rivett spent seven years as Princess Diana's personal trainer.
For four of those years, she told Insider she didn't know she needed to curtsy to Diana.
Rivett said she later tried to apologize but Diana laughed and said 'that's why I love you.'"
Princess Diana's personal trainer said she spent years not knowing she needed to curtsy to her.
Jenni Rivett told Insider she first started working with Diana in the early 1990s after she picked up a call from the royal's former butler, Paul Burrell.
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At the time, the South African fitness coach, who said she is also a clinical nutritionist, was based in the UK and was training one of Diana's best friends, Julia Samuel. Though she said finding out Diana wanted to work with her seemed out of the blue, she said the princess told her later she'd heard Rivett's name mentioned at three different dinner parties before reaching out.
"I just got a phone call one day. It was bizarre," she told Insider. "It was Paul Burrell from Kensington Palace, and he said, 'Oh, is that Jenni?' 'Yes.' 'Um, this is Paul Burrell calling from Kensington Palace and her Royal Highness would like to know if she could book an appointment to see you.'"
It's a moment that, even all of these years later, remains completely surreal to Rivett, she said.
"I was pretty blown away," Rivett said. After she got off the phone with Burell, she said she called her dad straight away to ask him to guess who her next client was.
"He said, 'I suppose you're gonna tell me Princess Di.' And I went, 'Actually, as a matter of fact, yes,'" Rivett said.
Off the bat, the two women got on, partly because Diana loved that she didn't grow up in the same social circles, let alone the same country, she said.
"I think we hit it off really well because she liked the fact that I was South African and I didn't know all the rules," Rivett said. "I didn't curtsy to her for four years because I didn't know I had to. Nobody told me."
After she found out, she said she was "so apologetic," something which Diana seemingly found amusing.
"She just laughed," Rivett said. "And said, 'Ah, that's why I love you because you're South African and, you know, please, you never have to curtsy to me.'"
Rivett currently offers online training sessions through her program, Train Like a Woman, which she said costs £35 (around $43) for 12 classes.