Georges De Keerle, Getty Images
Prince William and Kate Middleton paid tribute to Princess Diana earlier this week, U.K. newspapers report. The royal couple laid flowers at her grave site, an island known as The Oval, which sits on the Spencer family's Althorp Estate.
William has publicly stated that he wants his late mother to be present at his ceremony on April 29, saying that the engagement ring he gave Kate -- Diana's diamond-and-sapphire ring -- was "my way of making sure my mother didn't miss out on today and the excitement."
Prince Charles married 20-year-old Lady Diana Spencer in 1981 -- almost exactly 30 years ago from the date of William and Kate's upcoming wedding. In 1997, Diana was fatally injured in a car crash in Paris, after allegedly being chased by paparazzi. Her burial ground contains a shrine, which is a permanent memorial to the princess.
A royal spokesperson would not comment on the visit, telling the Daily Mail: "We cannot confirm or deny when either of the princes have made visits to the graveside of their mother for the reason that it is one of the most private aspects of their lives."
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