The endeavour is all in honour of their mother, Sally McLean-Butler, who was diagnosed with epilepsy when she was 10 weeks pregnant.
A few years later, the mum of two was also diagnosed with a brain tumour, which her children have called Boris.
While the 40-year-old is on an NHS surgical waiting list, the pandemic exacerbated the backlog and Sally does not know when she will be able to have the surgery.
Sally said: "I'm really really touched and overwhelmed that my children wanted to do this. I told them that I wanted to raise money for charity this year and when they told me they wanted to do it, it made me cry."
Her two children, six-year-old David and five-year-old Sophia, decided they wanted to raise money for the Epilepsy Society and take part in the charity's Challenge 100, where participants walk 100 miles in 100 days. They will be joined by their father, Kieren McLean-Butler, in their fundraising mission.
David and Sophia have learned how to call 999 and their mum's emergency contacts in case of a serious incident. They have already helped Sally on one occasion by running for their neighbour, who is a paramedic, when Sally was having an epileptic fit and broke her ankle while falling.
The mum of two has thanked the children's school, Market Drayton Infant School, for all of their help in taking care of David and Sophia, and for "picking up the pieces".
Sally said: "Epilepsy doesn't destroy you, but it takes a lot away from you. I can't swim with the children, I couldn't bathe them on my own, I can't drive.
"Not many people know about it. I wouldn't have known about it before I was diagnosed. People don't know how to react."