Sal’s mother, notable for her long black hair and adventurous spirit, whose vibrant personality influences the storyline despite her absence.

Sal’s best friend in Ohio, characterized by her anxious nature and imaginative theories, particularly following her mother’s unexpected disappearance.

Sal’s paternal grandfather, known for his cheerful optimism and love of life, who shares a deep bond with his wife, Gram.

Sal’s paternal grandmother, whose fun-loving and adventurous spirit complements her husband Gramps' nature, but she faces health challenges during a significant journey.

Sal’s father, known for his love of the outdoors and deep grief over his wife’s death, tries to adapt to life changes including a move to Ohio.

Phoebe’s mother, who fulfills the role of a traditional housewife but harbors hidden aspects of her identity.

A nurse and neighbor to the Winterbottoms, connected to Sal’s family through a significant shared experience.

A quiet and artistic boy at Sal’s school who forms a unique connection with Sal, reflected in shared creative expressions.

A mysterious young man searching for Phoebe’s mother, whose true relationship to her family is gradually revealed.

The blind, perceptive mother of Margaret Cadaver, known for her eccentric and lively personality.

Phoebe’s father, a practical and reserved man who faces challenges when his wife disappears.

Sal and Phoebe’s enthusiastic English teacher who inadvertently causes drama in the classroom with his lively teaching style.

Phoebe’s older sister, who is focused on personal ambitions and initially unaware of family issues.

A policeman in Euclid who handles the situation when Phoebe believes her mother has been kidnapped.

A lively and chaotic family in Euclid with whom Sal and Phoebe interact, symbolizing a contrast to their own families.

A sympathetic local lawman who assists Sal when she explores an area pivotal to her family’s past.

A boy who has an encounter with Sal’s family when they swim on his property but assists them during an emergency.

An old friend of Gram, known for her excitable and adventurous personality, who reappears after Gram’s passing.