DWIGHT, Ill. (WLS) -- A female teacher from Dwight High School has been charged with having a sexual relationship with an underage male student, the Livingston County sheriff said.Sheriff's deputies arrested 34-year-old Kathryn Patten at her home near the school Friday. She has been charged with criminal sexual assault by an authority figure.Investigators said the boy she allegedly assaulted is a student at the school, where she works.Dwight's superintendent said they asked police to investigate a rumor involving the teacher. That investigation led to the charges. Due to the victim's age and the circumstances, no further details are being released at this time, the sheriff said.Patten appeared in court Saturday and posted $25,000 bond.