Ten-year old Peggy Clayton and her two younger brothers, Teddy and Harry, live with their father, Dr. Clayton, and Nurse, a woman who has taken care of them since the death of their mother when Peggy was five.

Peggy is a sweet and kind little girl with a big imagination and a great sense of fun. Peggy's Trial follows her adventures with her friends at school, the mischief she and her brothers cause poor old Nurse, and even Peggy’s being chased by a bull. But nothing can prepare Peggy, Teddy and Harry when they fear they may lose their beloved father to a stepmother. (Summary by Lee Ann Howlett.)