The Cottage Grove, Minnesota, teen was diagnosed with a rare immune disorder at age 5, KARE reports.
"We were told that a simple sneeze could potentially kill our little boy, think of the boy in the bubble," Josh's mom, Katie Karels, wrote in an essay on Letsplayhockey.com.
As a young boy, Karels spent much of his childhood in the hospital, undergoing more than twenty surgeries. His illness eventually scarred his lungs, leaving him with just 40 percent of his breathing capacity.
"Throughout it all, Josh made every practice and every game, even if he couldn't skate," his mom wrote. "He sat on the bench and cheered his brothers on to victory after victory."
Then in December, Josh's family received a crushing diagnosis. The disorder had all but destroyed Josh's liver, bile ducts and pancreas. Doctors told Josh and his family that his case was now considered terminal.
Katie wrote about her son's hard-fought battle and lifelong love of the sport in an essay that elicited an outpouring of support for "Joshie Hockey," as he's come to be called.
"I have never seen anything like it," Katie told KARE of the response. "I never could have dreamed that we could be touched like this."
For now, Josh is coping with chronic pain and extended hospital stays, all while making it to as many hockey games and practices he can.
"Hockey, it helps me get out of the hospital bed, just knowing I have a game, I have to fight through it so I can go to the game and play. When I am on the ice, I don't hurt anymore. It all goes away," Josh told KARE.
His family is thankful for the sport that has continued to give their son a reason to keep fighting.
"So what is hockey to our family? Well, it is family," Katie concluded in her essay. "It is a community, it is support, it's a therapy like no other, it's a reason for fighting, and a reason for love. It is teammates sitting at a hospital bedside, day in and day out ... It is a game, a sport, and it is so much more."