For most people, completing three back-to-back marathons from London to Dover, rowing the English Channel, cycling 900-plus km to Verbier in Switzerland, hiking seven days across the Alps  to Zermatt and finishing by climbing the Matterhorn is a terrifying prospect. Not for 64-year-old Richard Branson and his son Sam, who are currently embarking on the gruelling challenge to raise funds for charity. The father and son are currently participating in the Virgin Strive challenge - an ultra-endurance fundraising event that started on August 7 and will end on September 6. Scroll down for video Challenge: Sam and Richard Branson are currently undertaking the Virgin Strive Challenge, which is made up of a series of gruelling challenges including climbing the Matterhorn. Here, they are joined by Isabella Calthorpe, Richard's wife Joan, Holly Branson and her husband Freddie
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Spoke to FEMAIL from Verbier
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He and son Sam undertaking Virgin Strive Challenge
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Isn't feeling phased ahead of the 10-16 hour climb of Matterhorn
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Raising funds for Big Change - set up by Sam and Princess Beatrice
Grandfather Richard: Sir Branson, pictured with newborn son Sam and daughter Holly in 1986, encouraged @placeholder's pregnancy and now wants Sam and his wife to have a baby too