A Terryville mother has been charged with manslaughter in the death of her 2-year-old daughter, Londyn, who was found to have a drug used to treat opioid addiction in her system.

Police arrested Rebekah Robinson, 31, of Terryville, on Tuesday and charged her with first-degree manslaughter, four counts of risk of injury and one count of tampering with a witness after an investigation.

That investigation started when state police responded to 211 Main Street just after 9 a.m. on Sunday Oct. 19, 2014 after the Plymouth Police Department contacted them to assist in investigating an untimely death of a 2-year-old girl.

The medical examiner's office determined the girl died of acute buprenorphine toxicity related to a drug used to treat heroin and oxycodone addiction.

Robinson told police her daughter had gotten into bed with her on Saturday after complaining that she was going to vomit, according to court documents.

Another family member called 911 on Sunday morning after the child was found unresponsive in the bed, police said.

Medics responded and transported the child to Bristol Hospital, where she was pronounced dead at 9:30 a.m., according to police.

A friend who had reported Robinson to police just weeks before the child's death told investigators that she had tried to report that if something wasn't done, Robinson was going to "kill" one or more of her children.

Three other children also living in the house with Robinson were unharmed, police said. Investigators described the apartment the family lived in as in deplorable condition with trash, moldy food, traces of feces and vomit, drugs and drug paraphenalia found throughout.

Court documents show that Robinson had been investigated by the Department of Children and Families at least four times before the toddler's death. The office of the child advocate is also investigating the death.

Police arrested Robinson after detectives from the State Police Western District Major Crime Squad, the Plymouth Police Department and the state Department of Children and Families investigated.

"Because the loss of any child whether by accidental or deliberate means is one child too many," Sarah Eagan, of the office of the child advocate, said.

A DCF report noted that Robinson has substance abuse problems and was diagnosed with bipolar disorder, opiate use disorder, cannabis disorder and borderline personality disorder.

As police conducted interviews, a woman told authorities that Robinson said she had an empty Suboxone wrapper on a mini fridge next to the bed where the child was sleeping on the morning the child was found dead and hid the packaging so police and paramedics could not find it, court documents state.

A toxicologist studying hair samples determined that the victim had opiates in her system for at least four to seven days before she died, according to court paperwork.

She is being held on a $750,000 bond and appeared in Bristol GA-17 today, where the case was transferred to New Britain. She is due back in court.

The court documents indicate there is some question as to whether the child's death was accidental as another friend told investigators that when robinson realized the child was dead, she "..hid the (suboxone) packaging so the responding police...would not locate it.."

"This child's loss...and loss to her family is a preventable tragedy," Eagan said.

Robinson's prior arrest record was mentioned in court, including a breach of peace and assault case, as well as an operating without insurance and following too closely case.