Having lost her husband Peter to cancer last year, Ms Mack said she and Caelan wanted to give back and help other families going through a similar journey with a loved one.
She said it was also important for Caelan to make sure his dad wasn't forgotten and to treasure the wonderful memories they made together.
"He was diagnosed with bowel cancer with secondary liver cancer in 2011. They gave him four months to two years and he survived for just over two and a half years," Ms Mack said.
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READ NOW"The Cancer Council helped us quite a bit with lots of things. It's an awesome service. We were really grateful to have them supporting us.
"(Peter) would be stoked we're doing the run."
She said family friends had also helped during the tough time by putting together funds to cover fun experiences for the family, memories Ms Mack said were priceless.
"Caelan remembers all the good things towards the end and he has some really good memories and photos of having these really nice times with his dad," she said.
Ms Mack said they wanted to be able to share that with other children and hoped to create a drive to pay for experiences " such as the Harley-Davidson ride and a car rally they enjoyed " for other families.
"We want other people to be able to get that opportunity because financially, you don't really have very much during those times and so it's difficult to be able to do anything," she said.
"Im going to talk to the Cancer Council and see if I can do some fundraising and set up some sort of foundation or something called Playing it Forward."
She said they were also grateful to Silver Chain and Caelan's school, St Stephen's School in Duncraig, which had also supported them.
"The school's principal and Caelan's teacher organised a busy bee at our house in the garden because Pete wanted everything to be nice for us when he passed away," Ms Mack said.
"It was all the teachers and their families, for the whole weekend they came over and cleaned up the garden and planted new plants. There were about 40 people at one stage digging, everyone was laughing and throwing dirt at each other. It was just incredible " they are such a lovely bunch of people."
To train for their 4km run, she and Caelan have been walking to work and riding to school.
Victoria said her biggest challenge on the day would be keeping up with her "energiser bunny" who would undoubtedly give her an incentive to run faster.
"I think he'll probably zip to the finish line faster than me," she said.
Caelan, a Year 5 student, said he was looking forward to the event which he said would be "fun" and just "amazing" to cross the finish line.
He has already donated his birthday money to the duo's fundraising page.
The pair hope to reach $2000 and have already raised more than $1300.
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