ST. LOUIS • A St. Louis woman was sentenced Friday to 78 years in prison after admitting to beating, whipping and waterboarding her children in a prolonged pattern of abuse that prosecutors described as "systematic torture."

Lakechia Schonta Stanley, 34, of St. Louis, faced 34 felonies, including multiple counts of assault and endangering the welfare of a child, for the abuse which was reported to a school librarian in October 2011.

One of the children, then 10 years old, had gone to school complaining of severe pain in her arm. Prosecutors say the girl revealed Stanley had beaten her with a baseball bat because she had not cleaned the kitchen quickly enough. The girl told the librarian that her sister, then age 8, was also beaten with a bat because she had taken too long to shower.

When the librarian examined the girl's arm she found it cold and hard to the touch, according to prosecutors. The girl was treated at the hospital, where it was determined that her arm had been subjected to such trauma that the blood supply to the limb was restricted.