Investigators say the boy's grandmother was given full custody of the child after Monticue was found guilty of neglect.
Laverne Monticue is described as black, 5 feet 3 inches tall, 150 pounds, with a medium dark complexion. She was last seen wearing brown pants, a brown blouse and brown sandals.
Anyone with information on the case is asked to call the L.A. County Sheriff's Compton station at (310) 605-6500.
City News Service contributed to this report.