What is the main event of Stuart Little?

In the movie Stuart Little, the main event is the journey that Stuart and Snowbell, the family cat, take to find Margalo, the lost bird belonging to Stuart's human brother, George, who has gone missing. Throughout the film, Stuart and Snowbell encounter various challenges and obstacles as they search for Margalo, including dealing with the mischievous antics of the neighborhood bully, a hungry falcon, and evading a group of cats led by Smokey, the alley cat. The movie's climax occurs when Stuart finally locates Margalo and arranges her rescue, leading to a heartwarming reunion between the bird and her family.