The siblings Charlie, 5, and Zara Millar, 3, suffer from Ataxia Telangiectasia - a rare and incurable disease often described as the worst parts of cerebral palsy, muscular dystrophy and cystic fibrosis, as well as being 1000 times more likely to develop cancer.

The little ones are two of only 40 children in Australia affected by the condition, with those diagnosed not expected to survive past their 20s.

Carly Millar, the siblings' mother, said their diagnoses came "as a huge shock".

"My husband Jeff and I are both carriers, which we were unaware of," she said.

"It was devastating news to receive, and to receive it twice was very upsetting."

Students from The Riverina Anglican College were tasked with designing a project under the International Baccalaureate Creativity, Activity and Service program, and 17-year-old college captain Holly Wilson's mind went straight to her family friends, the Millars.

"I've known the Millars most of my life, and it's just such a worthy cause to help them," she said.

"It's a horrific disease, Charlie and Zara are already starting to lose muscle control and lacking speech, and kids who are diagnosed are normally confined to a wheelchair by the age of 10."

Holly and four of her classmates decided to organsie a colour run and other sporting activities for the junior grades, separated over sessions to meet COVID-19 safety guidelines.

With a gold coin donation, the money raised from the events, as well as sock sales, will go towards funding research for the BrAshA-T foundation - Australia's only not-for-profit foundation dedicated to finding a cure for AT.

Mrs Millar said she and Mr Millar were "blown away" by the generosity.

"The support of the community has been fantastic," she said.

"We were really touched, it was such a kind gesture for Holly to think of us and a great initiative for the foundation as a whole."

Charlie and Zara will also be a part of a new trial set to begin in Brisbane, hoping to get a step closer to finding a cure.

"All the fundraising over the years has been able to see this trial get off the ground, it's the first of it's kind," Mrs Millar said.

"We're hoping for great results, and that it can help slow down the progression of the disease.

"But we are all just so grateful to Holly and TRAC, it's so generous and kind."