Left: Phillissa Diallo (Cherokee County Sheriff's Office). Right: Alyssa Rose Davis (Cherokee County District Attorney's Office).

A Georgia babysitter overdosed a 2-year-old girl with medication before she mutilated her, stuffed the body in a plastic bin filled with a "salt substance" and placed the remains in a closet.

Phillissa Diallo, 44, was sentenced last week to 37 years with the first 21 years to serve in prison for the death of young Alyssa Rose Davis, the Cherokee County District Attorney's Office said. She pleaded guilty to second-degree murder, cruelty to children and concealing the death of another.

The case unfolded on Dec. 14, 2022, when Diallo walked into the Canton Police Department and reported a dead child at her apartment on Hearthstone Landing Drive. Officers searched the apartment and discovered the remains in the plastic bin inside a closet beneath other items. Diallo refused to explain what happened.

An autopsy determined Alyssa had lethal amounts of acetaminophen and diphenhydramine, the prosecutor's office said. Acetaminophen is a pain reliever and fever reducer found in medications such as Tylenol, and diphenhydramine is an antihistamine found in medications including Benadryl. Alyssa was last known to be alive on Dec. 8, 2022. Investigators learned Diallo had been responsible for the girl over a two-week period.

But Ring video showed Diallo was not doing much babysitting. She left the girl alone in the apartment for extended periods of time and misled Alyssa's mother during their regular contact. Alyssa's mother was unaware of her daughter's death until cops notified her.

Diallo later admitted to cops that she found Alyssa in distress but declined to call 911. Had she called for help, Alyssa would still be alive today, prosecutors said. Diallo's defense attorneys claimed she was delusional at the time and suffered from anxiety and depression.

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"Instead of taking steps to preserve the child's health and well-being, the defendant demonstrated willful neglect. She then took gruesome, unimaginable steps to conceal her death," prosecutor Rachel Hines said in a statement. "Alyssa was not treated with the protection and dignity owed to every child, and that reality will haunt everyone involved in this case."

At sentencing, Alyssa's mother said she was "robbed" of her daughter. Alyssa's siblings "miss their sister deeply," the girl's mother said, and the family will never be the same.