"He wasn't even allowed to run," Rockwell said. "So, the kids, they made him the referee for every game. ... To be a part of it, in that way, was extremely important to him."
Chuckie passed away when he was 10 years old, several months before Blake was born. But Blake's life was deeply shaped by the brother he never met.
In the early 1990s, Rockwell became a volunteer at the children's hospital where his brother had been treated. For four years, he visited young patients one evening a week.
"So much of their lives were controlled by their illnesses ... we'd do whatever they wanted," Rockwell said.
He was surprised by how often these bedridden children wanted to talk about, or watch, sports.
"They were probably bigger sports fans than a lot of kids I knew who were healthy," he said. "But very few of them had ever been to a game, and that seemed absolutely crazy to me. I always wanted to take them to the games."
Since 2002, Rockwell has done just that -- and more. His nonprofit, Special Spectators, has given more than 10,000 seriously ill children and family members all-access, VIP experiences at college sporting events around the country.
Football season is Rockwell's busiest time of year. He works with children's hospitals to find families, then partners with universities to roll out the red carpet for them.
Game day usually starts off with a behind-the-scenes tour, where kids meet coaches and players and try on gear in the locker room. After that, families enjoy a tailgate that's often attended by cheerleaders, the mascot or the marching band.
Every event is unique. Recently, at the University of Oklahoma, children tried on diamond-encrusted championship rings in the head coach's office and sat at the anchor desk in the Sooners' broadcast center.
Families enjoy prime seats for the game, and usually the children walk onto the field and receive an ovation from tens of thousands of fans -- a moment that always gives Rockwell goosebumps. But he says the experience is about much more than going to a game.
"A lot of these kids, they're in it for a long haul" he said. "Their treatment protocol might be three years. And their tanks start to run low."
"Days like this restore the spirit in these kids to continue to fight."
CNN spoke with Rockwell about his work. Below is an edited version of the conversation.
CNN: Who gets to go to your events?
Rockwell: Our game day experiences are for the entire family, because they're all impacted by the child's illness. It's an opportunity for everyone to just relax and have a sense of normalcy.
We connect with them ahead of time to understand what their needs will be and coordinate that all in advance to make it easy, because their whole life is an ordeal. We want the families to just be there together and have a great time.
CNN: What kind of impact does the day have on everyone?
Rockwell: The coaches and players are phenomenal with our kids, and it's incredible to see these little kids hanging around...
Read More: Sick kids are VIPs at football games