Charles Spencer shared a lovely previously unseen photo with his fans on Sunday.
Taking to Twitter in honour of Mother's Day, he posted a black-and-white snapshot of his late mother, Frances Shand Kydd.
In the picture, she smiled as she looking down adoringly at the sleeping baby in her arms.
"Happy Mother’s Day to mothers everywhere," Princess Diana's brother captioned it.
His followers were quick to respond, sharing how much they loved the rare family image.
One replied: "Happy Mother's Day. Especially to Diana, these days I miss her so much." Another wrote: "Such a beautiful and charming Lady. Congratulations Sir."
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Others chimed in: "Gorgeous photo x," and: "Lovely picture."
The 56-year-old grew up with his three older sisters: Diana, Sarah, and Jane, and is now custodian of the Spencer family estate, Althorp House.
Last weekend, the Earl gave a glimpse into life with his family at the Northamptonshire residence.
He shared a snapshot on Twitter which showed a large projector screen on which a football game was playing, while a laptop in the foreground featured Charles giving a talk.
The Earl captioned the picture: "Good effort by one of my children last night: not missing the sport, while loyally following my live talk to their school on The White Ship...!"
In the background, a stunning white grand piano could be seen, along with a very comfy-looking leather chair, rows of picture frames, and a stylish faux fur rug.
His followers were clearly tickled by the self-deprecating message, with their responses including: "Hey! Priorities! Sorry dad! [laughing emoji]," and: "I hope they were supporting Fulham, Charles! All best."
Charles is a dad-of-seven, welcoming his youngest child, Lady Charlotte Diana Spencer, in 2012.
He tied the knot with his third wife, Lady Karen Spencer, back in 2011.
Lady Spencer has two adult daughters from her first marriage, while Charles is also father to the Honorable Edmund Spencer, 18 and Lady Lara Spencer, 14, from his marriage to Caroline Freud, as well four grown-up-children from his first marriage to Victoria Lockwood.
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