Charles Spencer has written a memoir about his sister, Princess Diana. The book, titled “Swan Song,” arrives nearly 30 years after her death.

Spencer, Diana's brother, frames the book around three subjects: her life, her marriage to Prince Charles, and the suffering she endured at the hands of the tabloid press.

The timing is the story's most concrete fact. Diana died almost three decades ago, and “Swan Song” marks the first full-length account of her life from a family member who knew her intimately. Spencer writes not as a biographer or a royal chronicler but as a brother.

The marriage of Diana and Prince Charles remains one of the most scrutinized unions of the 20th century, and Spencer's account places that marriage at the center of his sister's story. His narrative connects the private strain of that relationship to the public machinery that surrounded it.

The tabloid press is the third pillar of the memoir. Diana's treatment by British newspapers — the photographers, the headlines, the relentless pursuit — has shaped her legacy as much as any royal engagement. Spencer addresses that suffering directly, giving the subject a family member's authority.

What distinguishes “Swan Song” from the vast literature on Diana is its vantage point. Nearly 30 years of books, documentaries and television dramas have retraced her life from the outside. Spencer writes from inside the family, and his account carries the weight of witness rather than reportage.

The book also enters a changed conversation. Public attitudes toward the tabloid press, and toward the women it pursued in the 1980s and 1990s, have shifted sharply since Diana's death. A memoir that names her suffering at the hands of the press lands in a climate far more willing to assign blame than the one in which she lived.

For readers of “Swan Song,” the question the book raises is straightforward: what does a brother's account add to a story the world has told for three decades? Spencer's answer rests on proximity — to Diana herself, to her marriage, and to the pressures that closed around her.

Nearly 30 years on, the appetite for Diana's story has not diminished. “Swan Song” ensures that her brother's version of it will now sit alongside all the others.