SIOUX FALLS, S.D. (KELO) -- A former state prison employee has entered a guilty plea to one count of a prohibited sexual act between a prison employee and a prisoner.  UPDATE: 18-year-old dead in Monday RC shooting Cassandra Jelsma On Tuesday, 36-year-old Cassandra Jelsma entered a guilty plea in Bon Homme Circuit Court, according to the South Dakota Attorney General’s office. Jelsma faces a maximum sentence of two years in prison and a $4,000 when she is sentenced in Feb. 2025.  According to court documents, the incidents happened between November 2022 and June 2023 when Jelsma was a communications maintenance tech at the prison.