ELMIRA, N.Y. (AP) — A 24-year-old upstate New York woman faces a sentence of five to 25 years in prison for fatally poisoning her 21-month-old stepson.

Melissa Engelhardt was found guilty in late October of first-degree manslaughter in the poisoning death of Andrew Cianfrini in November 2009. Engelhardt was found innocent of second-degree murder in the bench trial in Chemung County Court in Elmira.

Authorities said Engelhardt admitted to police that she put antifreeze in the child’s sippy cup while he was visiting his father in Elmira.

The toddler lived with his mother in Batavia.

Engelhardt was charged in March after police said toxicology tests showed the boy had ingested methanol, a chemical commonly found in antifreeze.

Her sentencing is scheduled for Monday afternoon.

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