A brain-tumor diagnosis kept Jackson Tijerina from playing on his flag football team when he was 5 years old. 

Jackson, now 8, still loves football — especially the Iowa Hawkeyes. After being nominated for the last two years, Jackson will officially enter Kinnick Stadium as Kid Captain on Saturday. His mother, Amy Tijerina, says he’s more than ready for the role as a lifelong Hawkeye fan.

“He’s fully prepared, he’s ready for it, and he knows exactly what he has to do. He’s not nervous at all,” she said. 

In January 2015, Jackson began suffering from severe headaches, which led to his diagnosis with a brain tumor called pilocytic astrocytoma.

Although Jackson went through surgery and chemotherapy to remove the tumor in his brain, the tumor continued to grow. 

After a friend referred the Tijerinas to UI Stead Family Children’s Hospital, they began making the drive across the state from their hometown of Council Bluffs to Iowa City. 

Jackson began to see medical oncologist Mariko Sato at the Children’s Hospital. There, a new experimental therapy originally designed for adults with melanoma helped Jackson live like a kid again. 

“He’s been doing great on it. It’s been a total turnaround. He’s thriving, his tumor is starting to shrink, and he’s acting like a normal, healthy little boy now,” Tijerina said. “It’s been an amazing grace to go through Iowa City, because we feel like when all the other doctors gave up on him, they were the ones that didn’t.”

Testing revealed Jackson had a rare genetic mutation that caused his tumor to grow more aggressively than a typical case. 

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Sato said this type of mutation is very rare with only a handful of known cases. The new treatment is designed to target this specific mutation and has started to shrink Jackson’s tumor. 

“Since we started that, he’s started doing so well — he started gaining weight, he’s back to school. Until last year he was a more sickly kid, didn’t want to walk [down the] hallway, he didn’t want to play,” she said. “Now he can do things and he can try things.” 

Sato said the therapy has only been developed in the last three years, although she has a few other patients using the drug. 

Tijerina said besides football, Jackson loves country music and superheroes — he calls himself Iron Man because of the port for chemotherapy in his chest. Jackson received a video message of support from Robert Downey Jr. last year. 

Before being selected as Kid Captain, Jackson participated in a few other football teams. He has been invited to run onto the field with his cousin’s football teams and the teams at his parents’ alma maters.

RELATED: The Hawkeye Spirit: Children’s Hospital and Iowa football celebrate a decade of Kid Captain 

Jackson’s uncle Kevin Holden said he and his son came up with the idea of having Jackson run out with his cousin’s football team a few years ago, and Jackson loved it. 

“I think that’s one of the most special things we’ve been able to do with him. He just loves football so much, and he loves his cousins so much,” Holden said. “Now that he is going to be a Kid Captain for the Iowa Hawkeyes, all the little things he’s been doing have been leading up to this moment, and it’s pretty special that he’s able to do that.”