Michael Isaiah Thellmann

Michael Thellmann—a brilliant, determined, and complex soul whose life was marked by resilience, service, and a deep desire to bring healing to others passed away Sunday, October 11, 2026.

Born in Phoenix, Arizona, Michael moved to Oklahoma as a child and was raised by Timothy and Joy Thellmann alongside his younger siblings, Jonathan and Sunnie. From an early age, his remarkable intellect and force of will helped him overcome significant physical limitations.

Michael devoted four years to international missionary service with Youth With A Mission, including work in France and India. He later excelled in higher education and completed three years of medical school, pursuing his dream of becoming a physician and bringing healing to a broken world.

Michael overcame early physical disabilities through extraordinary determination. He served internationally for four years with Youth With A Mission, earned his degree while working long hours and maintaining top marks, entered medical school and completed three years of study, stepped away from school to serve as hospice caregiver for his birth mother, Deanna, continued seeking ways to return to medicine despite severe chronic illness and was an Avid musician and photographer.

Michael lived with Ehlers-Danlos syndrome, ulcerative colitis, rheumatoid arthritis, and profound personal struggles. Even under those burdens, he continued reaching forward. He found belonging among the close-knit friends he called his “tribe” and expressed love through practical, generous acts.

Michael’s final act reflected that spirit. While baking sourdough bread to share with his tribe, he collapsed after a sudden fainting spell associated with his physical condition. He died while doing something kind—nourishing the people he cared about.

Michael is survived by his parents, Timothy and Joy Thellmann; his siblings, Jonathan, Sunnie; and Carissa; his beloved tribe of friends in Oklahoma City; and extended family members. He was preceded in death by his birth mother, Deanna.

May Michael be remembered for his brilliant mind, his refusal to surrender, and the love he offered by continuing to reach forward.