Her admirers began paying tribute to the princess before dawn, placing candles shaped in the letter "D" at the palace gates.
Rivett was responsible for keeping the Princess in shape during the 90s.
Dubbed the world's most photographed woman, Princess Diana is remembered for her impeccable style and svelte body. Diana was real and open in a way a British princess hadn't been before.
Statue planned for Kensington Palace.
After the programme aired, thousands of people took to Twitter to praise the Princes as well as reveal they had been left "in tears".
"At first it just said she had a broken arm and I thought she'd be fine".
Kathy Martin joined the stream of visitors laying tributes to Princess Diana outside the gates of Kensington Palace on Thursday, just as she did 20 years ago.
It has been two decades since the auto accident that killed Princess Diana.
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Former members of staff will share their memories of her, alongside the hospital's patron, actress Linda Robson, and dancer Wayne Sleep. "It was pretty dramatic".
The princes commissioned the garden past year ahead of the 20th anniversary of their mother's death and were finally able to see it in full bloom on Wednesday.
Her untimely death shocked the world.
"I don't think there's anyone else like her now, she was a one off".
"I knew what my job was; it was to go out and meet the people and love them".
Fans who came out on the rainy eve of the 20th anniversary of Diana's death were given the opportunity to pay tribute - and at least one had an extra-close encounter with Harry. "We were similar age".
"This particular phase in my life is the most unsafe - my husband is planning "an accident" in my vehicle, brake failure and serious head injury in order to make the path clear for him to marry Tiggy", she allegedly wrote. I felt very lucky to do that.
They were handed flowers and messages by well-wishers.