A mentally ill Carpentersville woman will serve 25 years in prison for stabbing her older sister to death in 2014, authorities said. A judge Thursday sentenced 57-year-old Sandra L. Baumgartner to to prison for for the murder of 57-year-old Carpentersville woman Sharon Baumgartner, according to a news release from the Kane County State's Attorney's Office. Baumgartner, of 100 block of South Lincoln Avenue, pleaded guilty but mentally ill Feb.