Sarah determined to run like never before after niece's diagnosis

Vibrant Wagga toddler Grace was diagnosed with myoepithelial carcinoma - a rare cancerous tumour and will undergo a treatment which to be established by her oncology team at the Sydney Children's Hospital.

Sarah launched a fundraising campaign on Monday in a bid to drive financial support for Grace, Sarah's sister and Grace's mum Emily, her brother-in-law and Grace's father Ted and her nephew Paddy.

In just three days the campaign has raised more than $28,000 and will support Sarah as she prepares to tackle the Canberra Marathon.

"I had actually already planned on running the Canberra Marathon before Grace was diagnosed," she said.

"Once I found out the severity of Grace's cancer and what we were dealing with I knew I wanted to help in some small way.

"Experiencing the feeling of helplessness and not being able to change the news we wish we never received from the doctors - this was when I knew I wanted to run my first marathon for Grace and raise funds to support Grace, Emily, Ted and Paddy throughout this journey."

Sarah will set off on the 42.2 kilometre Journey on April 7 and is in the midst of preparing in the lead up.

"The thing I love about running is the mental challenge," Sarah said.

"It can feel so hard in the moment but the feeling you experience after is always worth it.

"Runner's high really is a thing. I've been running for quite some time now, however I have been following a structured running plan for the last 11 weeks with another five weeks to go before race day.

"I've been aiming for three-to-four runs per week changing between, intervals, tempo, easy and long runs."

Sarah is a member of Bunkr Gym and credits the team their for the confidence and knowledge she now house which she will be taking to the Race for Grace.

The funds raised through the campaign will be put into a trust for Grace to be accessed for ongoing medical costs.

With such a huge display of support and love shown from the community, Sarah has been left feeling heart-warmed.

"I am absolutely blown away with the support and so, so grateful for everyone's generosity towards donating," she said.

"At the same time I'm not surprised. Wagga is such a great community that support people and families who are going through difficult times."

Sarah will continue accumulating donations in the lead-up to the marathon and following through a GoFundMe Page that has been set up.

Donations can be made online at gofund.me/24a2fde7.