Is is not every year that a member of the royal family joins an official London Marathon competitor on the route - especially when it happens in Windsor.

But on Sunday Sophie, Countess of Wessex braved horrible wet weather to join Tomas Cardillo-Zallo, running alongside him on the Windsor Long Walk.

Tomas has learning difficulties and was running to raise money for Mencap - his own personal marathon taking him the 26.2miles along the Thames from Windsor to his home in Kingston.

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This year's London Marathon is very different from usual because of Covid - with only elite runners taking part in London and other fundraising participants encouraged to choose their own routes across the country.

The Countess of Wessex - who is Prince Edward's wife - is patron of Mencap. She ran with Tomas and his mum Sue for 1.5miles up the Long Walk to represent the 1.5million people in the UK with learning difficulties.

Tomas was one of 312 Mencap runners – including 10 with a learning disability – who completed the 26.2 miles challenge doing a route of their choice.

A relay of family members supported Tomas at other points throughout his marathon.

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The Countess said: “It was an honour to join Tomas even just for a small part of his triumph today, as he completes the virtual London Marathon in support of Mencap. Tomas has shown what people with a learning disability can achieve with the right support. He is an inspiration.”

Tomas said: “Thank you to Her Royal Highness for supporting me to run my first ever marathon. I loved every minute of running the 2020 Virgin Money London Marathon.”

Edel Harris, Chief Executive of the learning disability charity Mencap, said: "While Mencap runners didn’t have the race day they expected this year, with the support of The Countess and many others we have made sure that Mencap runners have had the day they deserve."