Emily has set up a Just Giving Fundraising page that you can see by clicking here. She has currently raised £1000.
Emily said: "As a competitive swimmer I had a big gap during lockdown with no access to a pool; so decided I needed a new challenge and that’s when I rediscovered my love for running.
"Over the past few months I have trained hard and worked my way from 3km to being ready for a half marathon.
"This weekend me and my dad will hit the streets of Aylesbury and aim to run my half marathon in about 2 hours and 30 minutes."
Emily is raising money for Cancer Research UK for Children and young people affected by this awful disease.
She addeD: "Please support me by donating to this amazing charity that supports children and young people who have been affected by cancer.
"I would also like to have some support on the day so will post my route and if you can come out and give us a cheer!"
Her mum, Hannah, said she was 'immensely proud' of her daughter.
Hannah said: "I was originally training with her but I stopped at about ten kim becuse I couldn't keep up!
"I'm so impressed. She's a natural swimmer and usually goes out 5 times, often early in the morning.
"She swims with Maxwell swimming club at Aqua Vale and The Guttman.
"Obviously being unable to do this, she's channelled her energy into running."
Emily has been out training hard with her dad, who is a keen runner.
Hannah had a lot of praise for her 'wonderfully determined daughter'.
She continued: "I honestly admire her so much.
"She's a very determined young girl. I think in a lot of respects it has helped her to keep busy and kept her mental health in good shape during the lockdown.
"She's been out a lot with her dad and has completely fallen in love with running, it's inspiring to see. "
Hannah has asked residents of Berryfields to keep their eyes peeled on Sunday morning near Lawson Way, and to cheer Emily and her father on if they see them out running.