Woman charged after boyfriend accused of raping, killing her 4-year-old son

A mother was charged Thursday in connection with the death of her 4-year-old son in Butler County, Pennsylvania.

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MacKenzie Peters was charged with felony child endangerment in connection with Bentley Miller’s death.

Peters' boyfriend, 20-year-old Keith Lambing, is charged with criminal homicide and aggravated indecent assault in connection with the boy's death.

According to a criminal complaint obtained by WPXI, Miller suffered abuse several days before he died. Police found a burn mark on the boy's hand, which police believe was from an iron. Investigators said Peters knew about the burn, but did not seek medical treatment.

The district attorney said he has no proof that Peters abused the child, but is not ruling out that she knew about past physical injuries. The complaint also said that investigators found drug paraphernalia in the motel room where Peters, Lambing, Miller and Peters' 4-year-old child had been staying.

Lambing’s mother, 43-year-old Kristen Lee Herold, faces charges of child endangerment.

The district attorney said Lambing had been watching the boy for a few hours at the Super 8 Motel in Butler while Peters was at work. According to court papers, Bentley suffered substantial injuries to his body, including cuts and bruises, and was sexually assaulted.

Investigators said Lambing called his mother, Herold, because the boy was in need of medical attention.

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Police said Herold was taking Bentley to his father's house -- not to a hospital, as initially reported -- when the boy stopped breathing.

Herold pulled into the parking lot of a credit union on Hanson and called 911, stating the boy was bleeding and unresponsive, police said.

Police said that when the boy was taken by ambulance, Herold allegedly went back to the motel to alert her son and to help him escape. Police later confirmed that the boy died of severe blood loss due to forced sodomy.

Police said they found Herold and Lambing hiding in an attic in a home in Butler on Wednesday.

"It's unthinkable, what happened to this little boy," District Attorney Richard Goldinger said Monday. "We're just going to try to get justice for him and his family.”

Cox Media Group