EVERETT — A baby girl who died last month with multiple untreated fractures from alleged abuse also tested positive for methamphetamine, Everett police said Tuesday.

The 3-month-old, identified in court papers only as “M.M.S.,” was tested at the hospital before she died, police Lt. Ryan Dalberg said.

How the child wound up with the drug in her system — and who caused her injuries — are questions in an ongoing investigation, he said.

The girl’s name was not confirmed by officials Tuesday. Her cause of death will be determined by the Snohomish County Medical Examiner’s Office.

The girl’s mother and the mother’s boyfriend were arrested Friday for investigation of felony mistreatment of a child. Hospital staff said not seeking medical attention for the baby’s broken bones exposed her to suffering they likened to torture.

Jerrica Schreib, 19, and her boyfriend, Donald Coons, 42, remain behind bars on $500,000 bail each. Coons also is awaiting trial on a meth possession charge from June.

“Further charges may arise as the investigation continues,” Dalberg said.

The sheriff’s office also is investigating the couple, who lived in unincorporated areas of the county before moving into an Everett motel Dec. 16. Authorities took the baby Dec. 18 after the mother called 911 after the girl became unresponsive.

The man’s daughters, ages 11, 13 and 14, were living with the couple at the motel. The girls have been placed in protective custody by the state.

“We are looking into the assault of other family members, including the other children who were with the couple,” sheriff’s spokeswoman Shari Ireton said Tuesday.

Everett police did not release news of the baby’s death last month while they conducted necessary interviews, Dalberg said.

“There was a high risk of flight with the two suspects,” he said. “They were basically transient.”

Detectives are collecting evidence, he said. The city’s major crimes unit and the special assault unit, which investigates crimes against children, are working together on the case.

The baby had a severely broken arm, according to court papers. She had never received medical attention for the injury, which appeared to be weeks old. She had other fractures, including broken ribs, plus a black eye and a gash on her chin. She also had pneumonia and meningitis.

During a search of the motel room, Everett detectives seized medicine, a thermometer, a baby bottle, droppers and drug paraphernalia. They initially were investigating the case as a second-degree assault, according to a search warrant.

In June, Coons was charged with drug possession. The incident occurred in Lake Stevens in November 2014.

At the time, Coons was in a van with a passenger. When a police officer said he might obtain a search warrant, Coons allegedly told him that a bag inside the van contained “a little bit of meth and maybe some heroin.”

Coons has adult misdemeanors for frequenting a place where drugs are used, domestic violence malicious mischief, violation of a protection order and driving with an expired license.

Court papers show Coons and his family have a long history of involvement with Child Protective Services. At least one of his daughters has been placed in protective custody before. He sought custody of the girl again in 2012.

Court records show years of domestic strife and allegations of drug and alcohol abuse involving Coons and the mothers of his children.

The mother of the two older girls was sentenced to jail after a 2012 forgery conviction. She admitted forging a document saying she was receiving drug treatment.

In a written statement, she said she “feared losing her housing and then her kids, and went on to describe a drug relapse, hospitalization for 29 days for an infection, the loss of her fiance (sent to prison), and an earlier CPS case at which time she fought her kids’ father for custody,” court papers said.

Rikki King: 425-339-3449; rking@heraldnet.com.