An inspirational eight-year-old from Southampton is climbing some of the UK's tallest mountains for charity - just weeks after his dad passed away.

Charlie Keen, who lives in Warsash with his mum Rebecca Roche, is spending his summer holiday finishing the three peaks challenge, which involves reaching the summit of England's Scafell Pike, Ben Nevis in Scotland and Snowden, officially known as Yr Wyddfa, in Wales.

Having already walked nearly 11,000 steps to summit Snowden, Charlie will climb Ben Nevis in Scotland today – on what will be his ninth birthday – before completing his challenge at Scafell Pike in September.

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He embarked on the difficult challenge in May, just three months on from the passing of his father, popular GB under-21 ice hockey coach Dayle Keen, in February.

His mum Rebecca said: “He’s amazing and blows everyone away each day, he has a real zest for life.”

The 33-year-old added: “That’s just the sort of person Charlie is, he’s incredibly selfless and always wants to help others even when he’s been through so much."

Charlie has spent time in and out of hospital as a result of suffering from severe asthma as well as separate renal problems and has seen first-hand the incredible support on offer for children and their families inside the NHS.

After becoming aware of Sophie’s Legacy – a charity that supports families who end up in hospital with their child – Charlie vowed to support the organisation the only way he knew how: by quite literally going the extra mile.

Charlie is raising money for Sophie's Legacy (Image: Supplied)

Since starting the challenge Charlie has raised more than £1,200 for the charity.

Rebecca said: “He’d have completed the three peaks challenge in 24 hours if he could, but I said that wouldn’t be quite possible as we have to do it when he’s not in school – and even if he has the energy to do it in that time, I know I don’t.”

Charlie has aspirations of becoming a doctor when he’s older, to continue helping others.

Rebecca said: “His family, friends, and teachers are consistently blown away by him, he’s a joy to be around.

“We’re all so grateful for the support, with Charlie surpassing his original goal of £1,000 he’s hoping to make it £2,000 by the time he reaches the summit of Scafell Pike.”

You can donate to Charlie's fundraiser here.