Salvador is a forty-pound Mexican American boy living in an impoverished neighborhood. Because his mother focuses entirely on a new baby, he acts as a surrogate parent to his younger brothers by preparing them for school and walking them home. He bears physical scars and carries an intense, undefined pain within his chest, and he reacts to his difficult circumstances with balled fists and quiet apologies. His intense caregiving schedule leaves him isolated, which prevents him from participating in recess or forming connections with classmates.

The Teacher is an instructor at Salvador's elementary school. Overworked or inattentive, the educator fails to learn Salvador's identity, notice his irregular arrival times, or recognize his struggles outside the classroom. This figure embodies the systemic neglect that working-class children often experience within educational institutions.

Mama is a single mother raising her children in a low-income household featuring raw wood doorways. Overwhelmed by the demands of a new infant and financial hardship, she delegates the parenting of her middle children to her oldest son. She maintains a practical, business-like approach to infant care rather than showing warmth. She also fails to protect Salvador from emotional and physical harm.

Cecilio is one of Salvador's younger brothers. Too young to manage his own morning routine, he relies entirely on Salvador to wake him, tie his shoes, comb his hair with water, and feed him breakfast. He trusts his older brother completely and holds his hand tightly during their walks home from school.

Arturito is Salvador's youngest school-aged brother. Still young enough to be clumsy, he regularly drops his cigar box of crayons in the middle of the street on the way to school. He depends entirely on his older brother's patience, and he reaches for Salvador's hand for protection and guidance when walking through the busy schoolyard.