FITCHBURG, Mass. —The mother of a missing 5-year-old boy did nothing to protect her son from abuse, a Massachusetts prosecutor has told a judge.

Jeremiah Oliver, of Fitchburg, has not been seen since September and is feared dead. His mother, Elsa Oliver, faces charges including reckless endangerment of a child. Her boyfriend, Alberto Sierra, faces assault and battery on a child among other charges. Both have pleaded not guilty.

Prosecutor Cheryl Riddle told Judge Martha Guzman during a sidebar at a court hearing in the case Tuesday that records from the state’s child welfare agency showed a pattern of neglect and abuse of Jeremiah and his siblings.

“She did nothing to protect the children,” Riddle said of Oliver, according to a transcript of the sidebar that was later made public by the judge. “Nothing to seek medical attention or get them help of any kind.”

Riddle also said Oliver expressed frustration with the Department of Children and Families’ involvement with her family.

A state social worker assigned to the family and a supervisor were fired earlier this month for their handling of the case.

The judge on Tuesday said Oliver could be released from custody if she can make $100,000 bail and meet other conditions, including wearing a monitoring bracelet, resolving a contempt case in juvenile court and dealing with mental health issues.

Oliver’s attorney, Gavin Reardon, said he can’t get useful information from her.

“She doesn’t seem to understand what’s going on,” he said. “I’ve been with her many hours and I can’t have a conversation with her.”

A competency hearing was scheduled for Jan. 10.

Guzman granted a request from prosecutors to hold Sierra without bail.

Oliver’s two other young children have been placed in state custody. The children’s father, Jose Oliver, said he will seek custody and he and other family members will continue to work with police in searching for Jeremiah.