Marilyn Arline Plassmeyer, 91, of Jefferson City, passed away Tuesday, September 22, 2020, at her residence. She was born on April; 13, 1929, the oldest daughter of the late George William Onken and Irma Davis Onken. In 1930, the family moved to Jefferson City. A 1947 graduate of Jefferson City High School, she attended Jefferson City Junior College and the University of Missouri. She was married on December 27, 1948, in Jefferson City to Anthony Francis Plassmeyer who preceded her in death on February 24, 2009. They made their home in Westphalia, Missouri, until 1967 when they bought a farm on the Osage River near Folk, Missouri. Marilyn was originally hired part-time by Three Rivers Electric Cooperative to edit their membership newsletter. Two years later she went to work for them full-time until retiring as Manager of the Members Services Department following thirty-two years of faithful employment. She was a founding member and past president of the Westphalia Historical Society. She was a recipient of several professional and civic community awards. In her retirement she was a volunteer in reading with Fatima Elementary and Cedar Hill schools for over fifteen years. She retired when she turned 89. Her proudest achievement was her family. She is survived by three children, Cheryl (Joe) Rutz, Washington, Missouri; Anthony "Chip" (Diane) Plassmeyer, Livermore, Colorado; and Joan (Dennis) Fick, Westphalia, Missouri; eight grandchildren, Shelby (Jay) Bunge, Labadie, Missouri; Carrie (Joe) Freese, Leslie (Joe) Haddox, and Anthony (Andrea) Rutz, all of Washington, Missouri; Curt (Katie) Plassmeyer, Estes Park, Colorado; Angela (Andrew) Matthewman, Windsor, Colorado; Ryan (Stacy) Fick, Jefferson City; and Casey (Adrienne) Fick, Columbia, Missouri; eighteen great-grandchildren; and a host of beloved nieces, nephews, and dear friends. She was preceded in death by one sister, Marcia Burwell. A Celebration of Life will be held at a later date. Her body was donated to the University of Missouri. Memorials are suggested to Jefferson City Animal Shelter, 2308 Hyde Park Road, Jefferson City, MO 65109; or Jefferson City Boys and Girls Club, 1105 Lafayette Street, Jefferson City, MO 65101. Dulle-Trimble Funeral Home, 3210 N. Ten Mile Drive, Jefferson City, MO 65091, is in charge of arrangements. Those wishing to send condolences to the family may do so at the www.dulletrimble.com website.