Week after week on 'Undercover Boss' (Sun., 9PM ET on CBS) we watch as corporate CEOs are touched by the lives of their employees. This week, Mack Trucks CEO Denny Slagle found himself particularly moved by Allan, an employee who keeps a positive outlook on life, while struggling to help his two grandchildren.

Both children have a genetic disorder that, according to their grandfather, is killing them. Treatments are expensive and not all of it is covered by insurance.

At the final meeting, when Slagle revealed himself to the employees he'd met, and tells them what's really been going on, he had a special surprise for Allan.

"This is from my wife and I, personally," he said, sliding an envelope across his desk. Inside was a personal check. "Just a little something to help defray your expenses for treatment or whatever it takes that might not be covered by the insurance."

Allan was understandably moved to tears by the gesture. It was perhaps a small thing for Slagle financially, but it was clearly a significantly important gesture for both men.