A spirited young girl spends a summer living with relatives on a riverside houseboat and confronts the small, everyday dramas of childhood and family life as autumn approaches. The plot moves through letters and errands, friendships with neighborhood children, school preparations, parties and seaside excursions, a Halloween-style fortune-telling episode, and a misunderstanding that causes anxiety before being resolved. Episodic scenes of household routine, youthful curiosity, and kindly adults emphasize themes of responsibility, loyalty, and growing up, with light humor and domestic detail carrying the narrative from one social occasion to the next.