She had a hand in the killing of MSU freshman Dustyn Frolka, now Samantha Grigg knows her penalty. The 18-year-old from Saline was sentenced in Clinton County Court on Tuesday to two separate terms. Five to 16 years for armed robbery and 5 to 16 years for manslaughter. Frolka was beaten in the back seat of a car Griggs was driving on I-69 near Bath when he jumped from the moving vehicle and was killed. Grigg will testify in the trials of two other teenagers who are awaiting trial.