A boy saved his sister from choking on a chicken nugget after learning how to perform first aid on John Cena’s episode of the Nickelodeon show The Substitute.

John Cena played a big role in saving the day for a little boy and his sister during a scary choking situation.

According to ABC affiliate WNEP, Pennsylvania native Jaxson Demsey, 8, was sitting in the backseat of his father’s car with his 20-month-old sister Leila when he noticed that she had started choking on a nugget. Thanks to an episode of Nickelodeon show hidden camera The Substitute, in which John, who now hosts Wipeout, stepped in as a substitute teacher and taught a classroom of kids first aid on a dummy, Jaxson knew just what to do to help his sister.

Jaxson told CBS affiliate WYOU of the scary situation, “It made me feel scared because I thought she was going to die. But then this thing came into my mind. I told my dad to pull over and I started to pat her back.”

It took Jaxson, who is in the second grade, 30 seconds to dislodge the nugget from his sister’s throat thanks to the technique he learned from John’s episode of the Nickelodeon show, which appears to be the Heimlich maneuver. He told WYOU that he feels “like a hero so much in [his] heart.”

“I would say thank you [to John Cena] for being on that show,” Jaxson added. “It taught me a lot about how to save someone’s life.”

Nickelodeon spokesman David Bittler said in a statement to E! News, “Everyone at Nickelodeon is so proud of Jaxson and his heroic actions, and we are honored to be a part of such a remarkable story of good news and courage! Yay for Jaxson and Leila!!!”.

The Substitute, which is currently in its second season on Nickelodeon, features stars going undercover in prosthetics to fool unsuspecting kids who have no idea they’re in the presence of someone famous. For John’s episode, he rocked a big beard and a fireman’s uniform to play the environmentalist and fire safety pro.