Last Updated Dec 2, 2014 6:57 PM EST
ANDERSON, Ind. -- A mentally disabled 15-year-old girl weighing less than 40 pounds was hospitalized Tuesday in critical condition while her grandfather and his wife were in custody on preliminary charges of neglect of a dependent after police said the girl was kept in a soiled, locked bedroom.
The girl, who turns 16 in less than two weeks, was in critical, life-threatening condition and could not speak to investigators, Anderson police Detective Joel Sandefur said.
Someone in the house, located 30 miles northeast of Indianapolis, called for an ambulance Monday. A nurse was using a device to keep the girl, who had feces on her feet, breathing when police arrived, the probable cause affidavit said.
The girl's 58-year-old grandfather was jailed Monday. His wife, who is not biologically related to the girl, was in custody Tuesday evening and police said she faced a preliminary charge of neglect of a dependent and battery.
No court hearings have been scheduled. Sandefur doesn't know whether either has hired an attorney. The Associated Press is not naming the man and his wife to protect the identity of the girl.
The man told police he was the girl's court appointed guardian because his daughter had abandoned the girl.
Police said the room where the girl was kept had a space heater, blankets, a bowl with oatmeal and a bucket and there was some blood on the floor.
The affidavit says the 225-pound grandfather admitted locking the girl in the room to protect himself, saying "she was very strong" and "she would approach him with a knife." A woman at the house told police that the man would sometimes drag the girl by her hair, the affidavit said.
The grandfather also told police she hadn't had a medical exam in nearly three years, and he could no longer afford to feed her a nutritional drink because her Medicaid ran out a year ago.
Police are trying to determine what the girl's disability is and what role it played in how she was treated, Sandefur said. The grandfather gave police a letter dated 2011 that says a chromosome problem in the girl's brain caused her disorder.
"It's our hope that at some point we'll be able to talk to her," he said.
The grandfather told police the girl had fallen Monday and several days earlier, and her condition had grown worse.
The affidavit says a 4-year-old who lives in the house told police the 15-year-old would stick her fingers out of the door trying to get out. Sandefur says he doesn't think the 4-year-old is related, and that the child was turned over to the Indiana Department of Child Services on Tuesday.