Earl Spencer is custodian of his family's Northamptonshire estate Althorp, and shared the latest beautiful find from the stately home with his followers on social media.
The father-of-seven wrote on X, formerly known as Twitter: "The attics at @AlthorpHouse have just yielded up another secret - this lovely, forgotten, portrait of my mother, in her very early 20s in the mid-1950s."
He shared a photo of a stunning portrait of Spencer family matriarch Frances, brought to life in shades of pink and grey, and the similarity to the late Princess Diana was incredible.
Charles' followers were quick to share their appreciation of the lovely artwork, with one writing: "Simply beautiful," a second adding: "Beautiful portrait of your mom [red heart emoji]," and: "Lovely portrait. Can really see the resemblance to Diana."
The late Princess was laid to rest at Althorp, and earlier this week Charles' wife, Karen Spencer, prompted an outpouring of emotion when she posted two emotive photos of Diana's secluded resting place on Instagram.
Fans loved the beautiful portrait
The Round Oval island on the estate could be seen shrouded in mist in the eerily beautiful photos, with Karen captioning them: "The Round Oval looking rather magical in the mist this morning." Karen's followers were enraptured by the hauntingly beautiful photos, which were also accompanied by a video of the area.
"Your husband chose the very best resting place for Diana. A place of beauty and silence," one follower wrote, while another added: "The perfect, most beautiful resting place for a princess. Diana was so loved."
Others noted that the setting is serene, with a third writing: "Feels serene and the sunrise looks like a heart-shape. Perfect." Karen was clearly taking an early morning stroll around the grounds, as she also posted a photo of the walkways glittering in frost.
Just last week he bemoaned that we weren't experiencing a cold snap yet, sharing a throwback photo of the frost-laced lawn at his home. "A wet, grey, morning today - so I’ve gone back a year, to when it was crisp, and especially beautiful," he reminisced.
Karen and Charles have a love of winter in common, as just yesterday Karen posted a photo of the property, peering into Wooton Hall, where Princess Diana learned to dance.
"Peering into Wootton Hall last night. I’m one of the few people who loves it when it gets chilly outside. Makes the warmth and cosiness inside even better," she said. Althorp is where Diana and her brother Charles grew up.
The sprawling abode, which was where the now King Charles first met Princess Diana, was previously owned by the late Princess of Wales' father, Earl John Spencer, but is now home to her brother, Charles, the 9th Earl Spencer, who lives there with his wife.
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The beautiful home boasts 90 rooms, 550 acres of land and, of course, The Oval, which is home to a temple dedicated to the late Princess, who is buried there. The estate also has a falconry, which Charles shared had been built for one week's entertainment in 1613.
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