Siblings and friends Ted Osborne, four, Alfie Osborne, six, Beatrix Osborne, three, Ava Mawdsley, six, Finn Mawdsley, three, and Isla Knight, six, are set to run the 1.5km of the mini run event on October 16.
They are hoping to raise as much money as possible for the city charity, which supports Ted who has Down Syndrome.
Alfie said: ‘I want to raise lots of money for Portsmouth Down Syndrome Association, because they help my brother Ted.’
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Isla agreed. She said: ‘I’m very excited.’
And Ava added: ‘I can’t wait to run with my friends.’
The association has more than 100 runners across the mini, junior, 5km and 10 mile Great South Run events – which will take place in Southsea over the weekend of October 16-17.
Among them are local firefighters Matt Burfoot and Craig Sadler who will be wearing their full firefighting kit and breathing apparatus to cover the 10-mile course on the Sunday.
Matt said: ‘I have a younger sister, Lucy, who has Down Syndrome and attends the Portsmouth DSA groups. She takes part in the activities and opportunities which give her the chance for development and importantly to enjoy herself with her peers.
‘I’ve run the Great South Run every year since 2015 and can’t find a better way to support a charity close to my heart, and I know the fundraising goes a long way.
‘Earlier this year I applied to join the RAF firefighter trade, and to get some firefighting knowledge I contacted my local station to help me with the process. Craig, who is in charge, supported me through a challenge to what will hopefully be my future career, so I thought it would be fitting to join him on a challenge he is attempting this year. Craig has a motto: “be the best version of you that you can be,” which I’m fully behind, and this challenge represents.’
To donate to Matt and Craig’s run visit uk.virginmoneygiving.com/MatthewBurfoot.
And to donate to the Fareham mini runners visit uk.virginmoneygiving.com/Team_Osborne.