Eight-year-old Tristan Regini loves his friend Cade Humphreys so much that when the Children's Hospital from Denver treated his friend's cancer, he decided to raise funds to help support the hospital.

Tristan set up a cocoa stand and sold hot chocolate in the freezing weather, and the young kid managed to raise $15. But when people started hearing about his cause, donations started pouring in from people all across America, and they have helped Tristan raise over $4,000.

"I've been more excited because I've raised more money," Tristan told 9News. "If there was no money at the Children's Hospital there would be no Children's Hospital."

Tristan believes that the Children's Hospital Cancer Ward is doing an amazing thing by saving kids's lives, and he will do whatever he can to help them.

"It's special, I think, because they're saving lives," he said. "I think that's a good thing."

His good friend Cade, also eight years old, is extremely touched by what Tristan did. "I thought that was so amazing. He's one of my best friends," he said. "He has spread the word. It was amazing. It makes me feel good."

Even Cade's father Seth appreciated what Tristan did. "It's been overwhelming. I think people like the positivity and they like seeing a kid to step up and actually influence things," he said. "It was unexpected, that's for sure. I think it just shows that it takes one person believing that they can make a difference and then executing it, and everybody wants to participate in that kind of thing."

There is now a website for the Children's Hospital Colorado Foundation with the title "Cocoa for Cade!" where interested individuals can donate to Tristan's cause. 

Cary Larger, senior vice president of the foundation told ABC News in a statement: "Each gift, whether large or small, is an investment in a child's healthy future and this gift is particularly meaningful because it demonstrates the youngest members of our community giving to enhance the hospital experience for his peers."