This time Rob was pilot and I was co-pilot. Our passengers were Kim and her brother Gary. The mission was to deliver Gary to Des Moines, Iowa. Gary was nervous about flying in a small airplane, and Rob was doing his best to assure him that everything was under control.
Rob demonstrated that if he took his hands off the control wheel, the airplane would continue to fly straight and level with little input. Suddenly the airplane veered off to the right and descended slightly. Quite startled, Rob grabbed the control yoke. Gary's eyes popped out of his head. I was the culprit. I had kicked the right rudder pedal, causing the unexpected right turn. I thought it was funny then, but I would not do that to a first time passenger again. Some things you learn with experience.