Nottinghamshire boy, 12, completes Three Peaks Challenge for sister

Jack said he wanted to help his sister Ruby and others in her position

A 12-year-old boy has climbed the highest mountains in Scotland, England and Wales to raise funds to research his sister's rare disease.

Jack, from Nuthall in Nottinghamshire, took on the Three Peaks Challenge to raise money for Pearson Syndrome.

His 18-month-old sister Ruby has been diagnosed with the rare DNA disorder.

Jack, who was accompanied in the challenge by his father Jonathan, completed the feat in 21 hours and 54 minutes.

He revealed the hardest part of the challenge was climbing Scafell Pike during the night.

"I'm very tired," he said. "My legs are hurting and I just want to lie down and chill."

Jack was joined by his dad Jonathan for the challenge

Speaking before he set off, Jack said: "Ruby's so funny and so happy but Pearson means her cells don't create enough energy.

"That means she gets really tired sometimes and I get sad when I see her like that."

Jack has smashed his fundraising targets

He and his father started by tackling Ben Nevis in Scotland, before driving to Scafell Pike in the Lake District and finishing with Snowdon in Wales.

Jack set out to raise £3,000 for The Lily Foundation - a charity that funds research into mitochondrial diseases, including Pearson Syndrome, and supports the families of affected children - but he has already more than doubled that target via an online fundraising page.

His dad Jonathan, who works as a police officer, praised Jack for his "strength, courage and determination".

Jack's family said they were "so proud" of him

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