Charles Spencer Honors Sister Princess Diana on All Souls' Day with 'Deeply Poignant Photograph'

charles spencer, princess diana
charles spencer, princess diana

charles spencer/instagram

Charles Spencer is thinking of Princess Diana.

The 9th Earl Spencer, 58, posted a tender tribute to his late elder sister and their father John Spencer for All Souls' Day Wednesday. Christians use the annual holy day to honor loved ones who have died.

"Today is All Souls Day — when it's customary to remember the souls of those you love, who've departed: it is known in some parts of the world as the Day of the Dead," Charles began an Instagram caption. "A deeply poignant photograph for me from the summer of 1989, when there was a party at Althorp to mark my father's 65th birthday earlier that year."

In the formal portrait, John was seated between his two youngest children. The father and son looked dapper in tuxedos while the Princess of Wales sparked in a champagne one-shoulder evening gown. Not pictured were Charles and Diana's two elder sisters — Lady Sarah McCorquodale and Lady Jane Fellowes — or their mother, Frances Shand Kydd, who got divorced from their father in 1969.

RELATED: Countess Spencer Launches Behind-the-Scenes Look at Althorp: 'Excited to Bring Everyone on the Journey'

Lady Diana Spencer, earl spencer
Lady Diana Spencer, earl spencer

Anwar Hussein/WireImage

John's birthday party was hosted at Althorp House, the ancestral home of the Spencer family in Northamptonshire, England, where Princess Diana grew up. The patriarch would face health challenges in the years that followed. In March 1992, he was admitted to the hospital with pneumonia. He later suffered a heart attack and died at age 68.

Five years later, in August 1997, Diana would be tragically killed in a car accident in Paris while being pursued by paparazzi. She was 36.

Her younger brother famously walked behind her casket at her funeral with Prince William, Prince Harry, King Charles III and Prince Philip. He also delivered a fiery eulogy at the somber service at Westminster Abbey.

Earl Spencer, who inherited his title upon his father's death, recently posted a photo of the "beautiful autumn colors" that surround the temple dedicated to Princess Diana at Althorp, along with a bit of the building's history.

"This temple, now dedicated to my late sister's memory, was originally commissioned by our ancestor George John Spencer. He was in charge of the Royal Navy in the early part of the Napoleonic Wars. In 1798 initial reports from Egypt said the British fleet had been destroyed in a crucial battle by the French. George John fainted with shock. When the true version of the Battle of the Nile followed, outlining what was an astonishing victory by Nelson over the French, George John had this structure built — in thanks to God," he wrote on Instagram last week. "It overlooks the Round Oval lake at Althorp and has become the place where kind visitors like to leave flowers in memory of Diana."

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Althorp is also Princess Diana's final resting place. Following her death, the late Princess of Wales was buried on an island at the center of the ornamental lake known as The Round Oval within Althorp Park's Pleasure Garden.

Family members can privately visit her gravesite, which is off-limits to the public. Visitors to the park, however, are welcome to pay their respects at the memorial site located on the grounds.

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According to the estate's website, Althorp is currently closed with plans to reopen next year.