But what many don't realise is that after Diana's death in 1997, her engagement ring actually belonged to Prince Harry.
A new documentary has revealed that Meghan Markle lost out on wearing Diana's reported $500,000 ring because a "selfless" Harry allowed Prince William to give the ring to Kate.
The Diana Story, an Amazon Prime documentary, featured an interview with Diana's former butler Paul Burrell, who confirmed the ring actually belonged to Harry.
After her tragic passing, Harry was able to select his favourite pieces of his mother's jewels and chose the beautiful sapphire and diamond ring.
Before William proposed to Kate in 2010, Harry offered his brother the chance to use the ring and honour their mother.
"Harry said to him: 'Wouldn’t it be fitting if she had mummy’s ring?'," Paul shared.
The former butler said the "selfless" act showed the qualities of Diana in Harry.
He added: "Then one day that ring will be sat on the throne of England. Harry gave up his precious treasure.
"His one thing he kept from his mother, he gave to his brother. That’s selfless, kind and exactly who Diana was."
Meghan was given a ring that featured a central stone from Botswana with two stones either side from Diana's collection.
The Duchess of Sussex said at the time it ensured Diana is "with us on this crazy journey together".
"Everything about Harry’s thoughtfulness and the inclusion of Princess Diana’s stones and obviously not being able to meet his mum," she said.
"It’s so important to me to know that she’s a part of this with us."
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