Charles Spencer took to social media on Sunday to reveal a special event taking place at Princess Diana's former home, Althorp House.
MORE: Earl Charles Spencer reflects on the Queen's legacy with touching message
The Earl shared that 600 cyclists had headed over to the estate for a charity bike in aid of the Cynthia Spencer Hospice, a charity set up in name of his late grandmother. The special evently was aptly named "Cycle for Cynthia".
WATCH: Charles Spencer captures rare magical moment at Althorp House
Charles shared updates on his social media accounts documenting the touching occasion. Captioning a photo of a keen bike rider and his young son, he penned: "I started one of the sections of #Cycle4Cynthia just now - a major fundraiser at @althorphouse on behalf of @CynthiaSHospice - Northampton’s hospice.
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"Humbling to see one of the 600 cyclists - Connor, with his proud father - was a full 55 years younger than me!"
Fans were delighted to see the touching update. One follower replied: "Great to see Earl Spencer," with an applause and red love heart emoji.
A second wrote: "It's a brilliant event. I'm sure lots of much needed money will be raised."
Charles updated fans on Twitter
A third added: "Thanks for letting this event start and finish at your estate. It was fantastically ran this year and well done to all the volunteers."
Last month, Charles shared a detailed insight into the life of his late grandmother, who would have turned 125 this year, in a segment of a documentary he uploaded to his Twitter.
The Earl explained that much like the impressive legacy of her granddaughter Princess Diana, Cynthia was " a stalwart of the local area, visiting farmers and villagers if they were unwell.
Princess Diana's brother recently opened up about his late grandmother Cynthia
He added: "She was very community minded it's a testimony to her popularity in this area that the hospice serving the local town Northampton is still called the Cynthia Spencer Hospice.
Charles also revealed: "She acted as the Queen Mother's closest confidants, she knew how to behave with everyone, she had impeccable manners but she could also charm the birds out of the trees, she had that wonderful presence."
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