An Iowa woman charged with kidnapping for confining her boyfriend's 8-year-old son under basement stairs has been convicted of a lesser charge.

A judge on Wednesday found Traci Tyler guilty of misdemeanor false imprisonment.

Prosecutors say she and the boy's father, Alex Shadlow, locked the boy in the basement of their Ackley home for at least nine hours a day in the summer of 2017. The boy told authorities he had to sleep on concrete.

Hardin County District Court records show that Judge James Ellefson didn't find that Tyler meant to inflict serious injury on the boy, a key component for a kidnapping conviction. Her sentencing is scheduled for April 26.

Ellefson oversaw Tyler's nonjury trial in Eldora. Shadlow's trial is set to begin Sept. 30.