Dennis William Kosek, beloved husband, father, and fisherman, died on December 23, 2025 in Waukesha, Wisconsin. He was born in Chicago, Illinois to William and Stephanie Kosek (nee Rajca) on April 13, 1944. Dennis married Carol Kapella in 1971. Dennis worked as a machinist at Western Electric in Chicago before transferring to Wisconsin. Dennis enjoyed fishing every summer on Rainy Lake in Minnesota. Dennis was active in the German Shepherd Dog Training Club of Chicago, Inc. He volunteered as a chaplain at Waukesha Memorial Hospital. Dennis is survived by his wife Carol, daughters Kristen Day (Craig), and Jenny Kosek (Matthew Lovison), and brother Kenneth Kosek. He was preceded in death by his parents William and Stella. A celebration of life for Dennis will be held Friday, January 2, 2026 at Wolniak Funeral Home 5700 S. Pulaski Rd. in Chicago, IL. 60629. Visitation from 9:00 am to time of Chapel Service 11:00 am Interment Resurrection Cemetery in Justice, IL.