Mr Wilson said his wife endured a four-year battle with cancer before dying on January 27. Initially the couple learned she had bowel cancer in 2010, which then spread to her lungs, pelvis and brain, he said.
"Rachel was a big advocate of it [Child Cancer Foundation]. It was more in honour of her than anything, to do my little bit for them.
"Anything and everything I can do for Rachel I certainly will do. I know she will be pretty proud of me to be involved in this kind of thing.
"There was a 16-year-old girl with beautiful dark long hair and bang off that came, so it is humbling to see who gets up and does it for these kinds of causes too."
Mr Wilson said his wife was loved by all those who met her.
"It's how Rachel was and even in her business, clients weren't just clients, they were friends as well. She had that personal touch with them."
Mr Wilson said his wife, who was a chartered accountant, was always a thriving, bubbling person with a ticking mind.
"She was friendly, helpful and would bend over backwards to help anyone.
"She wasn't one of these accountants who made $150,000 to $200,000 a year by punching numbers. She was an accountant who made nothing but helped a lot of people. That is how she got her happiness and enjoyed it."