Louis "Lou" Hepner passed away peacefully on August 4, 2025, in Sioux Falls, South Dakota, at the age of 89 years, 8 months, and 29 days.

Lou was born on November 5, 1935, in Chicago, Illinois, to Stanley and Julia (Sumoski) Hepner. The youngest of three children, he grew up in Chicago, where he developed a strong work ethic, a curious mind, and a lifelong appreciation for family, education, and good conversation.

A graduate of the University of Illinois, Lou earned a degree in Engineering and soon after moved to California's San Fernando Valley to begin his career. He worked for Hughes Aircraft, and among the many projects he worked on, Lou often said the highlight of his professional life was a special assignment at Kwajlein Island, part of the Marshall Islands. It was there his team worked with missile testing, and where he also formed lifelong friendships with Jack and Mary O'Rourke—bonds he cherished for the rest of his life.

After retirement, Lou settled in Sun City West, Arizona, and later relocated to Sioux Falls, South Dakota, to be closer to his family. In his later years, he found great joy in spending time with family and friends telling stories and listening to stories.

Lou had a sharp mind and a passion for understanding the world—especially through the lens of financial markets and investments. He enjoyed discussing financial matters, always eager to share insights or learn something new. As a young man, he also loved going hunting with his brother Ted and family, creating memories that lasted a lifetime.

Lou will be remembered for his intelligence, his thoughtful conversations, and the quiet strength with which he lived his life.

Missing Lou are his nieces and nephew, Dan (Carrie) Hepner, Sioux Falls, SD, Lisa (Stanley) Lynn, Sioux Falls, SD, Nancy DeWald, Kyle, TX and Sue Thies, Elizabeth, CO; 10 great nieces and nephews and 17 great-great nieces and nephews

He was preceded in death by his parents, Stanley and Julia; brother Ted and his sister who passed away as a young child, and nephew Steve Hepner.

Lou will be missed, remembered, and honored by all who knew him.