Princess Diana's Brother Posts Rare Sibling Photo as Bombshell Tell-All Book Hits the Stands

Today marks a big moment for Princess Diana’s brother, Charles Spencer. His new memoir, Swan Song: Diana, my sister, officially hits shelves, and rather than filling Instagram with the usual book-promo content, the 9th Earl Spencer marked the occasion with a throwback photo of himself and his late sister.

Taking to Instagram, Charles shared a black-and-white snapshot of the siblings sitting together on a window ledge. The pair appear to be wearing coordinating outfits, including jeans, dress shoes and hooded jackets. And unlike some of the other family throwbacks he has shared over the years, this one came without a caption.

The timing of the post is especially notable given the attention surrounding Swan Song ahead of its release. The memoir has already generated some controversy, particularly over Charles’s account of the aftermath of Diana’s death. The subject even prompted Buckingham Palace to issue a rare statement about a book.

According to ABC News, Spencer writes about then-Prince Charles’s reaction to his sister’s death and alleges that, during a disagreement over Diana’s funeral arrangements, Charles told him, "rest assured, we'll forget her soon enough," per the report.

In response, the palace told ABC News, "While we do not comment on books as a matter of principle, His Majesty is mindful that the pain of fraternal grief can cloud reason, affect judgment and color memory in ways others do not recognize, even many years after such a loss."

Charles has also been open about just how personal this particular memoir is. In the days leading up to its release, he shared a carousel of photos of himself holding the finished book.

"Always an amazing, and exhilarating, moment for an author to hold the first physical copy of a new book - and even more so for me with ‘Swan Song’, the most personal of the ten books I’ve written over the past three decades."

"At heart, this is a brother’s simple tribute to an extraordinary sister," the caption continued. "A month ago I read ‘Swan Song’ out, over three days, for a recording so that it could be available on audiobook. When I finished the recording, I thought: 'That is exactly what I wanted and needed to say - and she would, I reckon, have approved of every word.'"

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