AUSTIN, Texas — Eleven-year-old Bailey Lewis is on the move, climbing, jumping, bouncing off structures -- essential skills for parkour, or free-running.

In fact, he is a level two at a Tumble Tech Parkour Course in Cedar Park. He does this difficult sport with vision in only one eye.

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"As a result of my brain cancer, I lost vision in my left eye."

The 11-year-old was diagnosed with a brain tumor in kindergarten. He remembers the brutal treatments.

"There's a little port here that has a tube here that connects to my heart, and every Friday for five hours they would stick a butterfly needle in that right there and it hurt really bad. Numbing cream saved the day," the fifth grader said.

That's why he's raising money for St. Baldrick's Foundation, a charity that funds childhood cancer research.

He doesn't want other kids feeling like he did.

"I love helping kids going through what I've been doing," he said.

"It was very scary," said Bailey's mother, Gretchen Lewis.

Gretchen still remembers getting the cancer call when she was nine months' pregnant with Bailey's little brother.

"When the doctor called and said, 'Your son has a tumor behind his eye,' I said, 'Are you telling me my son has cancer?' She said yes. It was a really hard thing to hear," she recalled through tears.

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What's hard now for Gretchen is knowing the tumor may still grow, even though Bailey has been in remission since 2015.

That's why funding research is so important.

"They don't even treat it the same way as they did five years ago when we were starting this journey, so I'm very encouraged that one day if it does start growing that maybe they can do more for him," said Lewis.

For now, Bailey wants to continue raising money and awareness so he can help other children fighting cancer.

Bailey and two coaches on his St. Baldrick's team plan to shave their heads Saturday, March 30, at Dell Children's Hospital.

To donate visit the St. Baldrick's website.