Inside Princess Diana's final birthday and how her family will come together to celebrate her this year

Princess Diana’s sons and grandchildren are coming together to honor what would have been her 56th birthday on Saturday, July 1. Kensington Palace announced on Wednesday (June 28) that Prince Harry, the Duke and Duchess of Cambridge along with Prince George and Princess Charlotte will mark the somber occasion with a private service to rededicate the late Princess of Wales’ grave at her family's estate, Althorp House, in Northamptonshire.

Diana’s brother, Earl Spencer, and her two sisters, Lady Sarah McCorquodale and Jane Fellowes, Baroness Fellowes, will also be in attendance for the family event. The Archbishop of Canterbury will conduct the service, which is taking place about two months before the 20th anniversary of her death.

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VER GALERÍA The late Princess' sons and grandchildren are set to attend a service rededicating her grave Photos: David Goddard/Getty Images/Dan Kitwood/Getty Images

On her final birthday before her tragic accident on August 31, 1997, the mom-of-two was woken up to 90 bouquets of flowers and her youngest son, Harry, calling from school to sing Happy Birthday over the phone with a group of classmates. Diana was on dazzling form on her 36th birthday her brother recalled. Earl Spencer was by his royal sister's side at a gala held at London’s Tate Gallery, where the Princess was guest of honor at the invitation of director Nicholas Serota, whose wife Dame Angela was a friend through Diana’s work for AIDS patients.

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Earl Spencer poignantly said at his sister’s funeral just two months later, “The last time I saw Diana was on July 1, her birthday in London, when typically she was not taking time to celebrate her special day with friends but was guest of at a special charity fundraising evening. She sparkled, of course.”

VER GALERÍA Diana dazzled on her final birthday attending a gala in London Photo: Tim Graham/Getty Images

William’s mother looked radiant wearing a black chantilly lace sheath by Jacques Azagury that showed off her knockout figure. The eye-catching gown was a surprise birthday gift from the designer, who’d had it delivered to Kensington Palace that day. “Diana loved it. I believe she had another dress to wear but ended up wearing mine,” he told HOLA!’s sister brand HELLO! in an exclusive interview, adding that in the final stages of her life, “She was happier than I had ever seen her. There was something about the way she carried herself; a certain new-found confidence.”

Diana topped off her spectacular birthday look with one of her favorite pieces from the royal collection. Once worn by the Queen’s grandmother, Queen Mary, the emerald and diamond necklace was loaned to Diana for her lifetime. Her last birthday on July 1, 1997 was one of the few occasions after her divorce from Prince Charles that she wore heirloom rocks. Sadly that evening was the last such gala the Princess was ever to attend and many of those present would later be at her funeral. But that magical midsummer night summed up the essence of who she was, the beautiful People’s Princess who grew up before our eyes, learning along the way how to use her high-octane royal glamour for good.

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