Keith was the son of Arthur C. Oncken Sr. and Hannah Louise (Dietz) Oncken. Keith was born on April 19, 1932, on a farm south of Milledgeville, IL, the youngest of four boys.
Life was filled with hard work on the farm during the depression years, especially since his father died of tuberculosis when Keith was ten years old. Keith often rode his pony to a one room elementary schoolhouse and graduated from Milledgeville High School.
Keith married Evelyn (Lynn) Hull, the love of his life, on September 10, 1950. They met when Keith, captain of the basketball team, sprinted out onto the basketball court and knocked Lynn, a cheerleader, into the bleachers. They married young and had three daughters: Vicki Sandhu, Deborah (Bill) Crowson, and Kristy (Mike) Ford.
Keith embodied all the hallmarks of what we admire: a hard work ethic, commitment to family and community, a strong sense of right and wrong, and a genuine joy of connecting with people. Keith possessed a refreshing pragmatic approach to life, but what stood out was his authentic nature that adhered to truth and goodness. His exuberant spirit, affability, and kindness will be remembered by all who touched his life.
Keith farmed for 28 years as a dairy farmer and labored many long hours, but the earth was in his bones. He then worked for the Milledgeville Farmer’s Elevator as a grain operator for 39 years, retiring at age 84. He loved chatting with farmers and grain haulers during his career. Since his retirement, he had four mowing jobs in the summer months which he thoroughly enjoyed. Keith was a life-long Cubs fan, and for years he traveled to Milwaukee accompanied by his grandson, Christopher, to see the Brewers and Cubs play.
Keith’s civic involvements were impressive: he served on the Milledgeville School Board for 12 years; he served on the Carroll County Farm Bureau for 7 years; he was the Elkhorn Grove Township Supervisor for 53 years; he served as a volunteer or Fire Trustee (often as President) for 75 years for the Milledgeville Fire District.
Keith was preceded in death by his parents; three brothers; his wife, Lynn; and daughter, Kristy. He is survived by his daughters, Vicki, of Yorkville, and Deborah, of Dixon; son-in-law, Mike Ford, of Dixon; four grandchildren: Chris Diehl, Jamie (Tasha) Diehl, Nicole (Kevin) Garcia, and Alison Brantly; seven great grandchildren; three great-great grandchildren; and many nieces and nephews. He is also survived by special friend, Mirna Cabrera, whose extended family for many years has embraced Keith as a dear friend, surrogate father and grandfather. Our family’s appreciation of their love and support cannot be measured.
Visitation will be held at 9:00 a.m. on Saturday, January 24, 2026, at Messiah Lutheran Church, Sterling, IL. Funeral service will follow at 10:30 a.m. with Reverend Chad Bolosan officiating. Burial will conclude at South Elkhorn Cemetery in rural Milledgeville, IL.
In lieu of flowers, donations in Keith’s memory may be made to the Milledgeville Fire District.
Condolences can be shared at mcdonaldfuneralhomes.com.
