Dennis Michael O’Connor, M.D. Fortified with the Sacrament of the Holy Mother Church on Tuesday, February 3, 2026. Born on June 8, 1942 to the late Edward Jeremiah O’Connor and Emma Theresa O’Connor (née Mueller). He is survived by his teenage sweetheart and beloved wife of 61 years, Beatrice O’Connor (née Giuliani); sons Patrick (Kathryn), Michael (Deborah), and Bryan (Alyssa); grandchildren Sean, Tommy, Nick, Maura, Sarah, and Nora; brothers Dan and Robert; nieces, nephews, and cherished friends.
Dr. O’Connor graduated from St Louis University High School and St Louis University Medical School. He joined the Cardinal Glennon Children’s Hospital medical staff in 1964 as a medical student and then as the hospital’s seventh full time pediatrician, where he spent more than five decades, aside from a two-year military assignment to the Centers for Disease Control. He was triple-board certified in Pediatrics, Pediatric Hematology-Oncology, and Pediatric Infectious Diseases.
During his tenure at Cardinal Glennon, Dr. O’Connor served in many roles. These included director of student and residency programs, interim chairperson of Pediatrics, Vice President of Medical affairs, and Medical Director of the Footprints Palliative Care Program, which was one of the first pediatric palliative care programs in the United States. The Dr. Dennis O’Connor Chair of Palliative Care was established at St. Louis University in his honor. Guided by his strong faith, he believed deeply in helping children and their families receive the best medical care paired with the best quality of life care.
Dr. O’Connor also served as a member of the Cardinal Glennon Children’s Foundation Board of Governors from 2012 to 2023. He was honored to be selected as the recipient of the Dr. Peter Danis Award for Lifetime Achievement in 2015, and the prestigious Glennon Award in 2019.
Outside of his work as a physician, Dr. O’Connor served on the Garden District Commission, dedicated to helping transform the neighborhood around Cardinal Glennon. He was a member and former President of the Board for Vision for Children at Risk, which focuses on the welfare of children in the St. Louis community. He extended his care and compassion to everyone he met, from patients and their families, to friends and neighbors. He was a patient teacher and was always willing to lend a cheerful hand.
Dennis was frequently found walking his long-time St. Louis Hills neighborhood, cycling the city, maintaining his beautiful home and gardens, keeping the neighborhood birds well fed, and repairing his collection of antique clocks. As an avid cyclist, he once estimated that he had ridden over 100,000 miles, including completing the 700 Miles to Hope ride to benefit The Matthew and Andrew Akin Foundation in 2016, and a ride with cycling legend, Greg LeMond.
Dennis’ greatest joys came from serving children and their families, teaching the doctors of the future, and being with his family, of whom he was immensely proud. He touched many lives with his kindness, skill, and faith, and will be greatly and forever missed by all who knew him.
All services are private including internment at Resurrection Cemetery. In lieu of flowers, donations may be made to his long-time parish, St. Raphael the Archangel, 6047 Bishops Place, 63109.
Long time friend of his Brother Bert