Runner Erika Masna will do next Sunday’s Liverpool Rock ’n’ Roll marathon for Calne charity Hannah’s Trees.
The fund, set up in memory of 13-year-old Hannah Owen, helps to deliver Christmas trees to children in hospices.
Hannah, a pupil at Sheldon School in Chippenham, died of cancer in 2009 and the charity is run by her mother, Chrissie Lamb, of Bentley Lane, Calne.
Miss Masna, 37, of Warren Crescent, will be supported by partner Paul Callinan and children Lukas, six, Sofia, five, and Jakub, three.
She is a member of the Calne SMaRTT running club and came across the charity at the Santa Scamper at Calne Leisure Centre.
She said: “That’s when I first met Hannah’s mum.
“She was talking about it and it just gave me goose bumps. I thought how amazing they are able to pick up themselves up and do something for someone else.”
Miss Masna can be sponsored at uk.virginmoneygiving.