Police are searching for a 16-year-old girl who picked up her baby after work Saturday and vanished, according to the girl's mother.

Mercedez Estocado, a 16-year-old Castle High School student, and her 3-month-old baby, Skyylee, have been missing since 9:45 p.m. Saturday.

Mercedez's mother, Cathy Estocado, said at a news conference yesterday at police headquarters that the family is scared the girl is with her 18-year-old boyfriend, who is homeless and threatened to kill Mercedez and her family three weeks ago. He has a history of crystal methamphetamine and alcohol abuse, Cathy Estocado said.

Mercedez Estocado has a temporary restraining order against the boyfriend and police opened a first-degree terroristic threatening case in connection with the death threat, which was made over the phone, police said.

"It's common in the sense that when people make TROs they end up breaking them and getting back together," said investigator Phil Camero, a 10-year veteran of the department's Missing Persons Unit. "This is unique because a baby is involved."

Cathy Estocado said, "I don't know why she left, but she's been having trouble with her boyfriend. She just disappeared. She left for work and that's the last I saw (of her)."

Mercedez has a history of running away from home, her mother said, and usually returns within a week. But with a 3-month-old baby involved, the stakes are higher, she said.

Police are searching the Kahalu'u area where the Estocado family lives.

Mercedez Estocado took her mom's green Geo Tracker to work Saturday afternoon, Cathy Estocado said. Mercedez dropped Skyylee off at an aunt's house then went to her job making pretzels.

After picking the child up from her aunt's house, she disappeared, her mother said.

Reach Peter Boylan at pboylan@honoluluadvertiser.com.