Most parents, including Vernon Royal, have thought about the possibility of their son getting hurt on the football field.
"I worry about my kid getting injured and getting paralyzed," he says.
Johnson, 17, died Friday evening of an apparent cardiac concussion after a hit to the chest.
A recent study on sports deaths shows how rare cardiac concussions are. In the past several years, there have been 25 deaths, only one was a football player.
"The remaining occurred in baseball with a much smaller object than a football helmet or in hockey," says Sampson County coroner Carl Barr.
At Clinton High School's football practice, everyone was thinking of the accident which happened just 15 miles away.
"Our best wishes and prayers are with the Johnson family about what happened. It's a tragedy," says football player Stephen Horne.
Bob Lewis has been coaching for 30 years. He and many other coaches throughout the region talked with their players Monday about the tragedy.
"We told our players it was a freak thing that happened, and something like that happening again, the odds are low," he says.
Sudden death following a blow to the chest is called a heart concussion. The victims are usually young. Death is immediate and resuscitation is not possible.
Doctors also say it is very difficult to diagnose heart concussions, and not all cases are reported.