Princess Diana Would Have Been 56 Today, and Her Family Is Marking It in the Most Poignant Way

Princess Diana was remembered by her sons and close family in an intimate service at her family home on Saturday — the day that would have been her 56th birthday.

Her resting place on the island of the Oval Lake at Althorp House was re-dedicated in the presence of her sons Prince William and Prince Harry, along with Princess Kate and her brother Charles, 9th Earl Spencer.

William and Kate brought their children, nearly 4-year-old Prince George and 2-year-old Princess Charlotte, to the private service as well, which was led by Justin Welby, the Archbishop of Canterbury.

“The Duke and Duchess of Cambridge and Prince Harry will attend a private service to re-dedicate the grave of Diana, Princess of Wales at Althorp House on Saturday 1 July,” Kensington Palace said in a simple statement earlier this week. “The service, which will fall on what would have been The Princess’s birthday, will be conducted by The Archbishop of Canterbury and attended by her family.”

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Diana died following a car crash in Paris nearly 20 years ago, on August 31, 1997. She was laid to rest on the Oval Lake’s island six days later after a funeral service at Westminster Abbey. As the anniversary nears, William and Harry are set to unveil a public commemoration of their mother – a statue that will be erected in her honor at Kensington Palace.

Last year, Diana’s brother Charles, 9th Earl Spencer, told PEOPLE of plans to renovate the area surrounding the memorial, including the planting of forget-me-nots and rhododendrons. “They were Diana’s favorite flower,” he said last year. “I still remember giving her some when we were children. When I was six, I gave her a white pot of blue forget-me-nots.”