Jimmy is a man who works at a drugstore and is seen in the first film.
After Kevin begins backing away without paying for the toothbrush because of being scared by Marley and then turns and heads out, Jimmy was told by the clerk to stop Kevin. When he sees a police officer, Jimmy yells "Hey!", and a police officer looks up to see him (initially puzzled at what was going on). Jimmy then points out Kevin and says "Shoplifter!", and the police officer heads off after Kevin. Jimmy isn't seen in the film afterwards.