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Matias was diagnosed with neuroblastoma at 7½ months old

A tumor pressing against his spinal cord left him paralyzed from the waist down

Now 6, Matias is walking and continuing rehabilitation to improve his mobility

A 6-year-old boy who was paralyzed from the waist down as a baby after a tumor pressed against his spinal cord is now walking again.

Matias continues to undergo specialized rehabilitation at the Kennedy Krieger Institute, where he works on his strength, balance and movement, according to CBS.

During therapy, Matias practices stepping, balance and body control, using sensors and specialized exercises to help improve his movement and coordination. And when he’s given the option to try a different approach to an exercise, he has a straightforward answer.

“I can do it,” Matias said, according to CBS.

At the Kennedy Krieger Institute, Matias has worked with physical therapist Rachel Mertins since he was about 18 months old, per the outlet.

“He’s positive and he is upbeat, and he makes jokes, and he interacts with adults and the kids and everyone in this place and brings so much joy,” Mertins said.

But Matias’ road to rehabilitation began with a diagnosis his parents never expected.

Matias’ parents, Rachel Osborn and Jason Kling, spent five weeks trying to understand what was happening to their 7½ -month-old son, taking him to his pediatrician eight times as a number of unexplained symptoms emerged, according to CBS.

“We started noticing some symptoms that we really didn’t know what they were,” Rachel said. “They were kind of loosely connected.”

Still, the family didn’t have an explanation.

“We still didn’t have the answers,” Rachel told the outlet.

Tests revealed that Matias had neuroblastoma, a rare childhood cancer that develops from immature nerve cells, per the Cleveland Clinic. Doctors also found a tumor pressing against his spinal cord, according to CBS.

Surgeons removed what they could of the tumor, and Matias underwent chemotherapy to treat the remaining cancer, the outlet reported.

Then came another devastating development.

“Matias went to bed with full use of his legs and when he woke up the next time he was paralyzed from the waist down,” Rachel said, according to CBS.

Even after the tumor was removed, his family didn’t know how much movement he would ultimately regain, according to CBS.

Rather than wait, his parents began looking for ways to help him recover. Once Matias was medically cleared, they started physical therapy immediately.

“We knew that there was a really narrow window of time to start physical therapy,” Rachel told the outlet. “Literally the day that he was cleared we started physical therapy.”

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The family eventually learned about the Kennedy Krieger Institute from another family who had experienced a similar situation.

“We came to learn there was a world-renowned spinal cord injury center 45 minutes away from where we live,” Rachel told CBS.

His father also believes Matias’ identical twin brother has played a role in his outlook. Jason said having a twin who does not have the same mobility challenges gave Matias someone he wanted to emulate.

“The fact that he has an identical twin who is able bodied, I think that did a huge amount for his mentality and his spirit to know that he wanted to move like his brother,” Jason told CBS.

Read the original article on People