The Penderwick family consists of four sisters: Rosalind, Skye, Jane, and Batty. They enjoy adventures and share a close bond, often exploring the world around them. Their story begins during a summer vacation at a beautiful estate called Arundel, where they encounter new friends and face various challenges. The series, written by Jeanne Birdsall, highlights themes of family, friendship, and the joys of childhood. Each book follows the sisters as they navigate their lives, showcasing their unique personalities and the importance of supporting one another through life's ups and downs.