Prince William has reportedly declined to take part in a documentary about Princess Diana that his brother, Prince Harry, is said to be working on, according to British media outlets. The project, which is not yet confirmed, is part of Harry's ongoing efforts to reflect on the legacy of their late mother. It is speculated that Netflix, with which Harry is still under contract, may be involved in producing the documentary, as reported by The Times. Both brothers previously participated in a documentary titled Diana, Our Mother: Her Life and Legacy, released in 2017 to mark the 20th anniversary of Diana's death. In that film, they shared emotional reflections on their mother, describing her as a "loving mother" and calling the experience a genuine "catharsis" for William. At the time, the brothers stated they would never speak about her so openly again, acknowledging the deep sadness they felt. Ten years later, the relationship between the two brothers has changed significantly. As the 30th anniversary of Diana's death approaches, the brothers remain estranged and have not spoken to each other since their last encounter at the funeral of their grandmother, Queen Elizabeth II, in 2022. In July 2021, they both unveiled a statue honoring Diana in the gardens near Kensington Palace, but their personal rift has grown over the years. William reportedly does not forgive Harry for revealing details about the inner workings of the monarchy and expressing his grievances in an interview with Oprah Winfrey in March 2021, followed by the publication of Harry's memoir, Spare, in January 2023. Despite Harry's recent return to the United Kingdom with his family, the two brothers remain distant. The year 2027 will mark the 30th anniversary of Diana's death and is expected to bring many public commemorations. Diana's brother, Charles Spencer, has already released a book titled Swan Song: Diana My Sister, which criticizes King Charles and recalls the days following Diana's death. This has reportedly caused William discomfort, as he remains "deeply affected" by the loss of his mother. William has also expressed displeasure with the book's depiction of his father, describing it as portraying Charles with "exuberant joy" in the aftermath of Diana's death. In response, King Charles has issued a statement, stating that "the pain of mourning a brother could obscure judgment, alter perception, and color memories." William and Harry were just 15 and 12 years old when they lost their mother, and the memory of that trauma has remained vivid for both. They have spoken about their grief on several occasions, most notably in their 2017 documentary. William once said, "I think of her every day... My mother lives with me every day," while Harry remarked, "there is still a lot of grief to express." As the 30th anniversary of Diana's death approaches, the emotional and historical weight of this event will likely remain a significant factor in the lives of the royal family.