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Jewelry - Both Prince William and Prince Harry made sure their mother was an integral part of their engagements.

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Jewelry - Prince William gave Kate the same engagement ring that Princess Diana wore.

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Jewelry - Meghan Markle's engagement ring includes two diamonds from Diana's private jewelry collection.

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Jewelry - Prince Harry also gave his new bride an aquamarine ring, which Diana was seen wearing at a private viewing at Christie's in 1997.

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Jewelry - Meghan wore the ring to her evening wedding reception. The aquamarine stone is set in 24 carat yellow-gold and surrounded by solitaire diamonds, according to Elle.

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Jewelry - The Lover's Knot Tiara was a favorite of Diana's, who wore it on numerous occasions.

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Jewelry - The Duchess of Cambridge has also used the glittering headpiece several times.

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Wedding guests - Elton John was a great friend of Diana's, pictured here with the Princess at the funeral of Gianni Versace in 1997, just a month before she died in Paris.

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Wedding guests - Prince William and Prince Harry both invited Elton John to their weddings, and he even performed 'Your Song' at Harry and Meghan's lunchtime reception, says Harper's Bazaar.

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Wedding guests - Both Princes invited members of their mother's family to their weddings. At Harry's wedding, Diana's youngest sister Lady Jane Fellowes (pictured back left) gave a reading.

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Wedding guests - The Princes' uncle, Earl Spencer, also attended both weddings.

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Style - Diana's sense of style was iconic, whatever she stepped out in. Both Kate and Meghan often make references to her outfits, carrying on her classy, timeless elegance.

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Wedding music - The hymn 'Guide Me O Thou Great Redeemer,' which was sung at Diana's funeral, was sung at Prince William's wedding and also Prince Harry's in tribute to their mother.

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Flowers - Diana's favorite flowers were forget-me-nots and white roses.

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Flowers - St. George's Chapel in Windsor was decorated with white roses, peonies, and other flowers for Prince Harry and Meghan Markle's wedding.

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Flowers - Meghan's bouquet also included forget-me-nots, in reference to Diana.

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Sentebale - In 2006 Prince Harry founded his own charity called Sentebale, which means forget-me-not in Sesotho. The charity helps children and young people affected by HIV in Lesotho and Botswana.

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Flowers - Diana's treasured Sunken Garden at her former home in Kensington Palace was transformed into a temporary memorial known as the White Garden in 2017, to mark 20 years since her death.

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White garden - The gardens were planted with her favorite white roses and forget-me-nots, as well as scented narcissi, says the Telegraph.

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White garden - It was in this garden that Prince Harry and Meghan Markle announced their engagement in November 2017.

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Family - Diana broke a lot of traditions with her very hands-on approach to raising her children.

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Family - This parenting style is unsurprisingly being replicated by Prince William and the Duchess of Cambridge with their three children. 

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Family - The Princess took her sons skiing, to water parks, the beach, and on many fun outings.

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Family - The Cambridges also do the same with their young family.

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Family - Despite being a royal, Diana appeared fun and natural with her children in public.

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Family - Prince William and Kate also appear to be doting parents, managing to balance public appearances with child tantrums and tricks!

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Family names - Prince William's daughter takes his mother's name as one of her middle names: Charlotte Elizabeth Diana.

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Charity work - Diana represented a lot of charitable causes, at one point serving as patron to over 100, according to Harper's Bazaar, many of which her sons have carried on today.

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Charity work - Prince Harry has continued her work to fight the stigma against patients with HIV, forming his own charity, Sentebale.

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Charity work - Prince William is patron of Centrepoint, a UK charity which helps homeless individuals aged between 16 and 25. Diana took both her sons to Centrepoint hostels as children to help out.

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Charity work - Diana wished to be remembered as a "Queen of people's hearts," and her compassion towards the sick showed just that.

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Charity work - Prince Harry in particular has his mother's natural gift with people and has visited leukemia patients.

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Charity work - Prince William is equally good at engaging with causes for young and old!

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Charity work - Diana made history in 1997 when she walked through a live mine field in Angola. She drew the world's attention to the need to rid the world of land mines with The HALO Trust.

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Charity work - Prince Harry has continued Diana's mission with The HALO Trust, and pledged to have the world free of landmines by 2025.

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Mental health - Diana spoke openly about mental health and her struggles with postpartum depression. This was not something any member of the royal family had done before.

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Mental health - Harry, Kate, and William launched a campaign to normalize conversations about mental health in 2016, called 'Heads Together.'

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The Diana Award - The Diana Award was set up in 1999 to celebrate young people aged between 9 and 18 who are "courageous, caring, compassionate," according to Time. The Princes have heavily supported it.

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People's princess - Diana's title as the "People's Princess" is a testament to her ability to connect with the public, and her work for such a range of social causes.

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People's princess -

Today her sons and their wives show they continue to engage with people, just as she did.

See also: The most scandalous and rebellious royals

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