Peterson, Arnelda "Ardy", (nee Ritchey) of O'Fallon, Missouri, died on Wednesday, September 5, 2012 at the age of 90. Loving wife of the late Richard Lee Peterson; beloved daughter of the late William and Bernice Ritchey; devoted mother of Jeffrey (W. Jeanie) Peterson and Lance (Marianna) Peterson; grandmother of 5; great-grandmother of 8; step-grandmother of 1; step-great-grandmother of 3. She is preceded in death by her sister Gyrtha Brandt. Memorials may be made to Hope Lutheran Church.