A woman in southwestern Pennsylvania locked her 10-year-old grandson in a feces-filled dog crate for about 90 minutes because he told his family he had been spiking their drinks with lamp oil and household cleaner, police said.

Rhonda Lehman, 51, also called Washington County's Mental Health/Mental Retardation office and said if someone wouldn't come for the boy, she would bury him alive in the back yard, police said.

Lehman has custody of the boy, who told police he was lacing the drinks with the oil and a cleaner named "Bam" because "he was angry because he didn't get to go on a trip" last year, said Washington police Officer James Markley.

It is possible the boy had been spiking the drinks for a while, authorities said. Family members became sick, but were not hospitalized.

On Saturday, the boy was put in a 3-foot-by-4-foot plastic dog cage with only a small metal door for him to look out, Markley said.

Lehman was charged with child endangerment and making terroristic threats.

Police also charged the boy's 24-year-old brother with simple assault and harassment for allegedly punching the youngster.

"When I asked the brother, I said, 'Why would you punch a 10-year-old in the eye?' he said, 'It's better than what I wanted to do to him,"' Markley said.

Markley said the defendants told authorities they don't believe they did anything wrong.

"They were very calm, like this was nothing," Markley said.

Lehman and the boy's brother were in the county jail on $25,000 bail. Preliminary hearings are scheduled for Feb. 5. A listed phone number for Lehman could not immediately be found.

The boy is now in the custody of the county's Children and Youth Services, which is treating him for mental health issues, authorities said.

Washington is located about 25 miles south of Pittsburgh.