An older cousin from West Virginia who stays with the Finneys, quietly impacting the family dynamics while harboring his own secretive quest.

Mary Lou’s best friend, who is preoccupied with appearances and dating, leading to a shift in their friendship.

Mary Lou’s love interest, an athletic boy whose mutual interest and interactions with Mary Lou add a layer of adolescent romance to the story.

Carl Ray’s biological father, a character who adds complexity to Carl Ray’s personal journey and the narrative's exploration of family secrets.

Mary Lou’s father, a geologist and family man who balances discipline with affection in managing a bustling household.

The oral historian mother of Mary Lou, who manages household responsibilities while adapting to the presence of Carl Ray.

Mary Lou’s older sister, characterized by her focus on boys and social life, who contrasts with Mary Lou’s more introspective nature.

Mary Lou’s younger brother, who vacillates between childlike behavior and teasing his sister about her emerging maturity.

A quiet and serious young sibling in the Finney family, known for his good memory and distinct personality.

The youngest and most spoiled Finney child, whose innocent preferences hint at deeper instincts.

Carl Ray’s adoptive father in West Virginia, who exhibits a nurturing, yet traditional paternal role.

Uncle Carl Joe's wife, caught between supporting her son Carl Ray and preserving her husband's feelings.

The wife of Mr. Furtz, whose perspective and life change after her husband's death and acceptance of Carl Ray’s existence.

A popular, boy-focused classmate of Mary Lou’s, whose actions challenge Mary Lou’s sense of belonging.

An English teacher whose new presence prompts Mary Lou to consider how her personal writings will be perceived by others.