Princess Diana died following a car crash on Aug. 31, 1997

Charles Spencer, Princess Diana. Photo: Jon Kopaloff/FilmMagic; Tim Graham Photo Library via Getty

Charles Spencer is remembering his older sister, Princess Diana.

The 9th Earl Spencer, 60, shared a post on Instagram on Saturday, Aug. 31, commemorating 27 years since Diana was killed following a car crash.

Spencer shared an image that showed various photographs and newspaper clippings centered around Princess Diana, including one article about her christening and a photo of the late royal playing outside as a young girl.

He did not include a caption with his social media post.

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All About Charles Spencer, Princess Diana’s Brother and Closest Sibling

Spencer is the youngest of five children born to John Spencer and Frances Shand Kydd.

He grew up with his three older sisters: Sarah, the eldest, born in 1955, followed by Jane in 1957 and Diana in 1961. Spencer also had an older brother named John, who was born in 1960 but died just hours later.

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Following Princess Diana’s death, Spencer said he wondered if there was more he could have done to save his sibling. “You always think, God, I wish I could’ve protected her. It was just … it was devastating,” he told PEOPLE in 2017. “I always felt … intensely protective towards her.”

Since Diana’s death, Charles has become an outspoken defender of her legacy and champion of her causes.

Charles Spencer, Princess Diana. Amanda Edwards/WireImage; Tim Graham Photo Library/Getty
Charles Spencer Shares Rare Childhood Photo with Sister Princess Diana and Their Mom

Spencer was the one who gave the eulogy during Princess Diana’s funeral on Sept. 6, 1997.

Serving as “the representative of a family in grief, in a country in mourning, before a world in shock,” he paid tribute to his late sister as the “very essence of compassion, of duty, of style, of beauty.”

Spencer also called out how Diana was treated by the tabloid media, describing her as “the most hunted person of the modern age.”

While later speaking with PEOPLE, Spencer reflected on the moment and said the line “summed up so much of the anger I felt toward those who had done that to her.” He added of his eulogy, “In the final paragraph I had run out of energy, almost out of oxygen. I had to punch each syllable out of the base of my stomach.”