The Duke of Sussex sent flowers to his mother's grave for Mother's Day, HELLO! has learned.
A spokesperson confirmed that Harry arranged for flowers to be laid at the grave on Sunday.
Diana, Princess of Wales died in 1997, when Harry was just 12 years old.
Both of her sons have been keen to carry on her legacy of human rights work, with her youngest presenting the first virtual Diana Award last year.
The Duke gave a special mention to those who have been awarded for their work on issues related to race and injustice, saying: "I am so incredibly proud to be part of these awards as they honour the legacy of my mother and bring out the very best in people like you…
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"I know that my mother has been an inspiration to many of you and I can assure you she would have been fighting your corner.
"Like many of you, she never took the easy route, she never took the popular one, or the comfortable one. But she stood for something. And she stood up for people who needed it."
The Duke and Duchess of Cambridge also paid tribute to the late Princess on Mother's Day, sharing letters written by their children to "Granny Diana" on their official Instagram account.
The late princess was a devoted mum
In the first letter, seven-year-old Prince George wrote: "Dear Granny Diana, Happy happy Mother's Day. I love you very much and think of you always, sending lots of love from George xxx."
The little boy had also drawn Diana a beautiful picture of a sunset, trees and birds flying in the sky.
The second letter, accompanied by love heart and stickers, was written by Princess Charlotte, five.
The little girl wrote: "Dear Granny Diana, I am thinking of you on Mother's Day, I love you very much. Papa is missing you. Lots of love Charlotte xxx."
The third letter featured an adorable love heart drawing from two-year-old Prince Louis, which was accompanied by his name.
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