The charity, of which the Earl is a patron, is the largest dedicated funder of research into brain tumours and according to Charles more needs to be done to help support the organisation.
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Taking to Twitter the Earl wrote: "More funding is needed to fund research into brain tumours. "So many young people are taken by this relentless disease. Condolences to all who loved and admired the talented Tom Parker.
"I’m proud to be a patron of @BrainTumourOrg which is doing great things & aims to do even more."
Charles posted the heartfelt message to Twitter
Charles' plea was met with appreciation from his followers. One replied: "Thank you for this post. My condolences to Tom Parker’s friends and family."
Another commented: "A terrific charity that I have taken great pleasure in supporting through @Iggygolfday & a golf competition I run."
The Earl's message comes after The Wanted band member Tom Parker sadly died from a brain tumour aged 33 on Wednesday, leaving behind his wife Kelsey and their two young children Aurelia and Bodhi.
On Tuesday Charles marked a sad anniversary as he took to Instagram to post a tribute to his late father, John Spencer, who died 30 years ago.
John Spencer outside his home in Northamptonshire
The Earl shared two pictures of his dad and the father-son resemblance could not go unnoticed. The first picture was a photograph taken of John "in his dashing youth" and the second was a more recent oil painting.
Friends and fans of the Earl couldn't wait to tell him how much he looked like his father. Cynthia McFadden wrote: "What a handsome man— you look so much like him — sending love to you and Karen."
One fan wrote: "God bless your Dad. What a beautiful picture. You look just like your Dad."
Others couldn't help but notice other family resemblances, as one fan commented: "I can see William and Harry in this photo." Another said: "Wow! I see Diana in his face and Prince George. Lovely photos."
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