These two kids have a thing or two to teach adults about true friendship.

When Missouri first-grader Zac Gossage, aged 6, was diagnosed with acute lymphoblastic leukemia last June, his best friend Vincent Butterfield, aged 7, was right there by his side for support.

And when Zac began losing his hair because of chemotherapy treatments, Vincent didn’t want him to feel any different from other kids. So, like a true friend, he shaved his head to match.

I cut it off to make Zac feel like he’s not the only one without any hair,” Vincent told KSDK.

That’s not all Vincent’s done. Since Zac’s diagnosis, Vincent has been trying hard to understand what his friend is going through, asking questions to figure out what cancer really means.

It’s when your white blood cells and your red blood cells fight,” he said.

And when Vincent found out that Zac’s treatment was costly, he wanted to help with that too.

Vincent’s mom, Karen Butterfield, recalls, “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.”

Vincent and his mother sold more than 20 scarves, raising about $200 for Zac.

As for Zac, he’s managing his treatment well. Despite frequent hospital visits, he barely ever misses school. And he wants to keep it that way, “because I get to play with Vincent outside at recess,” he said.

He’ll continue to receive treatment for the cancer, which has high survival rates and is most common in children aged two to five.

For now, Zac and Vincent are just happy to hang out with each other.

When asked what friendship is, Vincent looked at Zac before stating, “It’s a beautiful thing.”