Through an arrangement with the father, Wendy Cervantes picked up Bryan Bazan about 7 p.m. Wednesday. The boy's father, who has sole custody of the child, said he was to have been returned at 6 a.m. Saturday.
The father, Elim Bazan, later learned from a relative that Cervantes planned on taking the boy to Mexico where she has family.
"I want to get my baby back and I hope he's OK," Bazan said. "She knows what kind of father I am. I've never done that to her. I didn't deny the baby to her, even though we have problems. I allowed her to see the baby."
"Bryan's mother has close family ties in Guadalajara, Mexico, which is where it's believed she may have taken Bryan," said Sgt. Mathew Jacobik of the Los Angeles Police Department.
Bazan said he believes Cervantes may have fled with the boy because she's due in court Monday in connection to a domestic violence charge in which she allegedly attacked Bazan and the baby.
"I'm the one dealing with the baby pretty much the whole time when she doesn't have him," he said. "He means everything to me."
Bazan said he thinks one of Cervantes' family members may be driving her south of the border.
Anyone with information is asked to call the LAPD at (877) 527-3247.
City News Service contributed to this report.