UNION, MO (CNN) -- A Missouri first grader knows the meaning of friendship better than many adults. And he's proving it to his buddy, who's battling cancer.
At Central Elementary in Union, Missouri the best teachers may just be two students. First graders Vincent Butterfield and Zac Gossage are very good friends and often very silly.
But recently there wasn't a lot to laugh about. Last June, after feeling ill and tired for weeks, Zac was diagnosed with acute lymphoblastic leukemia, a fast-growing cancer of the white blood cells. Zac's mom Stacy Tooley said, "As a parent, you want to make sure nothing bad ever happens to your child and when something does you want to be able to fix it. And I couldn't."
Still, while everybody around him took it hard, Zac took in stride. Despite frequent trips to the hospital, he almost never missed a day of school.
As for Vincent, he started asking questions and learning about cancer. He said, "It's when you're white blood cells and your red blood cells fight."
Then he learned that Zac's treatments were expensive. Vincent's mom Karen Butterfield said, "We had been making these scarves and he just kind of said it would be cool if we could make a whole bunch of these and sell them."
He sold more than 20, earning a couple of hundred dollars.
Vincent also found out that Zac might lose his hair because of the chemotherapy treatments. So one day, he showed up to Mrs. Koester's first grade class wearing a stocking cap. His teacher Adrienne Koester recalled the conversation saying, "And he said, 'Mrs. Koester I have a surprise for Zac.' And I said, 'Well, you do, yes I do.' And he pulls off his stocking cap and here I see that he shaved his head."
Vincent said, "I cut it off to make Zac feel like he's not the only one without any hair."
Zac continues to get treatments and continues to come to school every day. And Vincent? Well he may be young, but he's teaching us the oldest lessons. He said about friendship, "It's a beautiful thing."