Gandy's sidekick is a dog named Sourpuss. He is known for his grumpy expression, which contrasts with Gandy's cheerful personality. Despite his name, Sourpuss is loyal and always ready to help Gandy on their adventures. Sourpuss has a unique ability to sense danger, often alerting Gandy before trouble arises. His keen instincts and playful antics make him an essential companion. Together, they navigate various challenges, showcasing the strong bond between a dog and his owner.