Sonia Espinosa is Carlos Espinosa's mother. She came into the Philadelphia Police Station one day, asking Detective Rush to investigate the murder of her son, Carlos, who died of asphyxiation after spray paint was sprayed into his mouth. Back in 1982 (though not shown), Sonia worked three jobs, so she rarely saw Carlos. From her own assumption, she assumed Carlos was a paint huffer. She was none the wiser. She was let off from her job at the time of "Bombers", and couldn't pay for storage. She brought up Carlos' murder when she found his tagging blackbook.