Delphine is a responsible eleven-year-old girl who acts as a surrogate mother to her two younger sisters. Raised in Brooklyn by her father and grandmother, she travels to Oakland for the summer to stay with her estranged mother. She is highly observant and protective, carefully managing the family's travel money and ensuring her sisters are fed and bathed. Her time in California challenges her traditional views on race and proper behavior.

Cecile is an independent poet operating a printing press in her Oakland kitchen. She left her family in Brooklyn nearly six years ago and writes under the pen name Nzila. When her daughters arrive for a summer visit, she refuses to assume traditional maternal duties. She instead directs the girls to attend the local Black Panther community center for meals and childcare.

At seven years old, Fern is the youngest of the Gaither sisters. She travels everywhere with a white, blonde-haired doll named Miss Patty Cake. This attachment draws criticism from adults at the community center, but Fern holds onto the toy as a source of comfort. Though quiet and frequently dismissed as a baby, she pays close attention to the world around her.

Vonetta is the middle Gaither sister and the most socially adaptable of the three. She thrives on attention and quickly makes friends upon arriving at the People's Center. She often bristles against Delphine's attempts to parent her. When forced to choose between family loyalty and peer approval, she sometimes prioritizes fitting in.

Big Ma is the paternal grandmother to Delphine, Vonetta, and Fern. Originally from Alabama, she stepped in to raise the girls in Brooklyn after Cecile abandoned them. She holds traditional views on behavior and race, repeatedly advising her granddaughters to stay quiet and avoid drawing attention to themselves.

Louis is the father of the three Gaither sisters and the estranged husband of Cecile. He remains in Brooklyn while sending his daughters to California for a month-long visit. He provides financial support but takes a hands-off approach to daily parenting, expecting Delphine to manage the care of her younger siblings.

Sister Mukumbu is a dedicated teacher at the Black Panther community center. She runs the morning breakfast program and teaches the children about civil rights. She creates an encouraging environment for the Gaither sisters, using scientific concepts like the Earth's rotation to explain the natural progression of social change.

Crazy Kelvin is a vocal, confrontational man who spends time at the People's Center. He frequently lectures the children on political ideology and openly expresses his disdain for the police. He particularly targets young Fern, publicly shaming her for carrying a white doll.

Hirohito is a neighborhood boy of African American and Japanese descent who attends the summer program at the People's Center. He spends much of his time riding his go-kart down local hills. He is dealing with the absence of his father, a Vietnam War veteran who was recently imprisoned.

Eunice is an Oakland local and the eldest of three sisters. She quickly recognizes Delphine's role as a surrogate parent to her siblings. The two bond over their shared responsibilities, though Eunice occasionally teases Delphine about her budding interest in boys.

Janice is Eunice's younger sister and a regular attendee at the community center. She quickly bonds with Vonetta Gaither, giving Vonetta a peer group independent of her own sisters.

Mrs. Woods is Hirohito's mother and a caring member of the Oakland community. Despite dealing with her own husband's unjust arrest, she demonstrates profound kindness by offering the Gaither sisters food and a safe haven when they are left without adult supervision.

Bobby Hutton is a historical figure and a teenaged member of the Black Panthers who was killed before the Gaither sisters arrive in Oakland. His death heavily impacts the local community. The adults and children at the People's Center organize a rally in his memory to protest police violence.

Huey P. Newton is the historical co-founder of the Black Panther Party. Though he does not directly interact with the children, his principles shape the curriculum at the People's Center. His teachings on fighting inequality influence the racial ideology the Gaither sisters encounter during their summer visit.

Lady Ming is the owner of the local Chinese takeout restaurant down the street from Cecile's house. The Gaither girls give her a nickname based on her severe, efficient manner when taking their orders. Despite her brusque exterior, she is an established business owner in the neighborhood.