Speaking on Fox Sports programme League Life, Kimmorley said he feels "very empty" when he wakes up but is determined to help others going through difficult times. It was clear from his very first answer of the night the 40-year-old was struggling. His voice was cracking and he was doing his best to hold back the tears.
"It's something that's very special for us as a family to try and push forward and help someone else not have to go through it. That's literally why I'm doing this this week," Kimmorley said.
"Until you're around it [cancer] you don't know. It impacts you in a sledgehammer way when you became a part of it.
"What really caught me out was when you go to the cancer clinics, how full they are. How much of it there is out there and the fact it's underfunded and the fact if there's any way you can help get some funding and get a solution to the problem because it's horrible.
"The cause is very special. The NRL has an enormous power to convince people, to persuade people, to encourage people to donate money and to buy a beanie to support something that has very little funding. Even my children themselves who've done their own things to help mum ... they did Relay for Life last week.
"We started as a family and we finished as a family. Everything we do is an 'us' decision, not so much a 'me' and 'I' decision. I think they raised $10,000 or $11,000 for Relay for Life themselves."
Kimmorley was hurting most when talking about his kids, and he was too emotional to find the words when explaining his desire to carry on Sharnie's legacy.
"It's trying to take something that Sharnie tried to say to us last year, that she could handle it," Kimmorley said. "We had a softball game last year that was all to raise money for the Mark Hughes Foundation so someone else doesn't have to go through it.
"It's like trying to carry that [legacy]."
Kimmorley's had to deal with so much of late he says he forgot the Beanies for Brain Cancer round was this week before he was reminded last Thursday.
The former playmaker admitted it's been hard since Sharnie's death because his family is based in Newcastle and he lives in Sydney, but said close friends and his children have helped him during the most difficult time in his life.
"It's something you probably don't know how to handle. I feel very empty, waking up. But the support you do get from the NRL and friends helps," Kimmorley said.
"My four daughters ... they're your sole focus, that gets you through each day. I don't look ahead very far, I look day-to-day and I roughly know how I'm going.
"It's very isolated and you feel lost and empty, so you certainly need people to ask questions. Family have certainly been great but they're all based in Newcastle so you rely on your close friends and the people around you.
"It's like the big family has to stay together and rally together."
Viewers took to social media to praise Kimmorley's "heartbreaking" appearance.