CALDWELL -- A Caldwell woman is behind bars after police say they discovered her infant daughter underfed and near death from starving.

When police encountered the baby March 8, 2016, the eight-month-old weighed just 11 pounds, well below average for a child that age, according to court documents.

Officers had been called out to the home of 21-year-old Tiffany Knapp to help Child Protective Services perform a welfare check on the girl after receiving a report that she was "severely malnourished and underweight," the documents say.

According to a Caldwell Police report, the child had been given only Kool-Aid and watered-down milk for sustenance.

Medical records say the baby had been born three months premature and had had difficulty gaining weight since her birth. Police say she had been prescribed a specialized formula designed to help infants put on weight. Doctors stressed the baby needed the formula in order to stay healthy, but Knapp did not fill the prescription and never contacted the doctor's office or any pharmacy, police say.

Police say Knapp at first denied receiving a prescription, then admitted she was aware of the prescription but had "just spaced it."

Lack of proper nutrition was medically determined to be the cause of the girl's low weight.

The baby was declared to be in immediate danger and was taken into the custody of the Idaho Department of Health and Welfare. She was taken to West Valley emergency room, where police learned the infant "would have likely died of malnutrition within days of being seen had she not received medical attention due to lack of nutrition and proper care," according to court documents.

The child was placed into foster care, where she gained more than four pounds over the next 20 days, police say.

A warrant was issued for Knapp in the case Sept. 21. Canyon County spokesman Joe Decker said it took more than six months to bring charges because prosecutors wanted to make sure the case had been thoroughly investigated.

Knapp was arrested Sunday. She's currently held in the Canyon County Jail on a $50,000 bond, and is due back in court Oct. 11.

Felony injury to a child is punishable by up to ten years in prison.