Otto, age 97, died at Sturgis Regional Senior Care Center. He was the son of Otto and Lydia M. (Tarrisslo) Wanhanen. He married Beulah Nelson on December 18, 1939, in Sturgis. Survivors include his wife, his daughter, Barbara Aman, two grandchildren, three great-grandchildren, and his brother, Waino Wanhanen. He was preceded in death by his parents. A private interment was held at Nemo Cemetery.

On December 18, 1939 Otto married Beulah Nelson. They were  married for 67 years. The couple moved to Moskee, WY, and Beulah, WY. They returned to the Black Hills and lived at Chicken Ranch south of Strawberry Hill before buying the farm on Old Ridge Road in March of 1943.