A Pennsylvania mother confessed Wednesday to killing her 3-year-old daughter while under the influence of a combination of illegal drugs and prescribed medications.

Regina Lester, 33, pleaded guilty but mentally ill to the June 2016 third-degree murder of Isabel Godfrey, who died of multiple blunt force trauma, had various bite wounds, and showed signs of asphyxia. Officers who responded to the Chesapeake Estates mobile park found Lester naked and hugging a tree, and claiming she needed to kill her neighbor’s children, according to the York Daily Record.

The York Dispatch reported Lester had fentanyl, K2, marijuana, and the anti-anxiety drug lorazepam in her system at the time of the murder. The defense referred to a report from the prosecution’s expert psychiatrist which stated that Lester was enduring multi-substance use disorder and noted she was experiencing a slew of mental-health issues, including bipolar disorder, depression, anxiety, and possibly schizophrenia.

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Before cops’ arrival, Lester reportedly told a neighbor that she killed the toddler to get the “darkness” out of her, according to the news outlet.

Lester claimed she regularly smoked K2 and would occasionally smoke it marijuana. However, she claimed it was the first time she took bath salts.

“I wasn’t myself,” the mother said, per the Daily Record. “I blacked out.”

Senior deputy prosecutor Kara Bowser said she wasn’t charged with first-degree murder because the cocktail of drugs and prescriptions diminished her capacity, meaning she lacked intent to kill Godfrey.

Defense attorney Suzanne’s Smith said Lester’s mental health diagnoses came after she suffered a severe head injury during a car accident which occurred in her 20s. The attorney claimed Wednesday that Lester has remained heavily medicated since the slaying.

“Every day she lives with this…She does feel bad (and) she misses her kids,” Smith said of the mother. “I don’t even know when she realized her daughter was dead and that she did it.”

Sentencing is scheduled for June 27. Lester faces 20 to 40 years in prison if the judge accepts her plea.

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[Featured image: Regina Lester/Jackson Township Police; Isabel Godfrey/WPMT video screengrab]