ST. LOUIS COUNTY, Mo. — A Jennings, Missouri, woman is accused of child endangerment after a toddler she was babysitting died last month of a drug overdose.

It’s the fourth reported incident of a child dying of an overdose while in her care.

The St. Louis County Prosecuting Attorney’s Office charged Mary Curtis, 30, with one count of first-degree endangering the welfare of a child – death of a child. She’s being held on a $1 million cash-only bond.

According to Sgt. Tracy Panus, a spokeswoman for the St. Louis County Police Department, the child died March 20.

A probable cause statement obtained from county police says Curtis was responsible for watching the child, a 17-month-old, for several hours. During that time, another child indicated that the 17-month-old had fallen asleep on the floor.

Police claim Curtis took the toddler to another home, where they called 911 over concerns for the child’s safety. The toddler was rushed to a local hospital and pronounced dead.

A toxicology report indicates the toddler had fentanyl and xylazine in her system, which caused her death.

Panus said investigators determined the child was in good health when left in Curtis’ care, and was unconscious when brought to the second home to contact police.

Curtis was already out on bond for another fatal drug overdose involving a child in St. Louis City. She also has two other child overdose cases on her record, both of which resulted in deaths.