John M. Kostrey M.D. John Kostrey, a pediatrician who cared for patients at the DeKalb Clinic and Kishwaukee Hospital for more than 40 years, passed away peacefully at Oak Crest Health Center on March 8, 2026. He had been in declining health for several years. Born (Jan Kostrej) in Czechoslovakia in 1934, he was a child survivor of WWII. In the early 1950s, he served his obligatory year of military service and worked in the iron ore mines in the Spis Region of eastern Czechoslovakia. He graduated with a medical degree from Charles University (Prague) in 1959, after which time he worked for several years as a physician in various regions throughout the country. In 1965, he defected from Eastern Bloc communist Czechoslovakia to Sweden, seeking freedom from socio-political repression. While waiting for his U.S. asylum case to be approved, he was granted a temporary visa to work in a medical research lab in Stockholm. After his asylum to the U.S. was granted, he applied and became a naturalized U.S. citizen in 1970. He taught himself English and confirmed his professional credentials, completing his medical internship at MacNeal Memorial Hospital (Berwyn) and medical residency at Milwaukee Children’s Hospital. Dr. Kostrey came to DeKalb in 1969 and began working for DeKalb Clinic. He found the farming landscape of DeKalb County to be reminiscent of his native Slovakia and ideally located in a small university town near cultural opportunities offered in Chicago and Rockford. He met his wife Millie, an elementary school teacher, in the Chicago Slovak community, and they married in 1970. They raised four children together and were married for 55 years. Dr. Kostrey was a pediatrician with a particular interest in infectious diseases. He worked at DeKalb Clinic and Kishwaukee Community Hospital from 1969 to 2012, serving as Chief of Staff at one time. Dr. Kostrey retired at age 78, albeit reluctantly, striving to never stop learning. He was a caring, well-known, and well-loved physician in the community. He delighted in seeing his patients grow up over the years, and he would often be stopped by former patients at local community events and gatherings who remembered his good humor and smile. He is survived by his wife Mildred (Millie), and his four children; Elizabeth (Andrew) Hall, Julie Kostrey, Allison (Timothy) Hapeman, and John (Michael Golterman) Kostrey. Eight grandsons; Ian, Miles, and Lucas Hall, Lawrence, Calvin, Samson, and Amos Hapeman, and Charles Kostrey. He is also survived by relatives in Slovakia including sister Anna. He is preceded in death by his parents, his sister and brother. Dr. Kostrey’s family wish to express their gratitude to the staff at Oak Crest and Northern Illinois Hospice for providing such compassionate care. His children are grateful for a father who personified strength, courage, resilience, care, and discipline, and who instilled a strong work ethic and respect for life. In lieu of flowers, memorial contributions may be made to St. Jude Children’s Research Hospital https://www.stjude.org/donate/donate-to-st-jude.html?sc_icid=header-btn-donate-now or a charity of your choice.Funeral service will be held on Saturday, March 14, 2026, at 11:00am at Hillcrest Covenant Church in DeKalb with Pastor Jen Zerby officiating. Visitation will be held on Saturday, March 14, 2026, from 10:00am until the time of service at the church. Burial will be immediately following the service at Fairview Park Cemetery in DeKalb. Arrangements were entrusted to Finch Funeral Home 310 Oak St. DeKalb IL 60115 815-758-3841.