The boy's father found him in the mother's house Friday night in the small southeastern Utah city of Toquerville near the state line with Arizona, Washington County Sheriff's Office Lt. David Crouse said on Tuesday.
Authorities found feces throughout the bathroom, one blanket, a few empty cans of beans and a camera that may have been used to capture what was going on in there, Crouse said. The boy was likely kept in the dark, he said. Investigators found 3 square feet of duct tape mounted on the light switch so it could not be turned on. The door had locks on the outside.
The boy, who was unable to stand on his own and weighed 30 pounds, was taken to a hospital where he is expected to remain for weeks to recover, Crouse said. The doctor who treated the boy says it is the worst case of malnourishment he had ever seen, Crouse said.
The 36-year-old woman was charged Monday with felony child abuse.
The Associated Press is not naming her to avoid identifying the boy. Her lawyer did not immediately return a call for comment.
The boy's two siblings told investigators their brother had been in the bathroom for at least one year. They said they hadn't even spoken to their brother through the door in six months, Crouse said. He declined to give their ages, but said one was old enough to understand things.
"It is one of the most horrible things I've ever had to see," Crouse said. "I wish I could unsee it."
The woman's two other children have been put in custody of state child protective services. Investigators are talking with those kids to determine if they had been abused, Crouse said.
The probable cause statement shows the mother told detectives her son chose to sleep and stay in the bathroom. She says she would occasionally lock him in the bathroom for his own safety when she left the house.
The statement says the mother said she was trying to feed her son protein shakes to increase his weight.
She is being held on $20,000 bail, and expected to be back in court on Jan. 17.
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