Mark Edmond Mittelstaedt passed peacefully on June 12, 2025, at Sacred Heart Medical Center in Spokane, Washington. He was born on March 3, 1939, in Portland, Oregon, alongside his twin sister, Marcia. He also had an older brother, Robert. In 1940, the family moved to their homestead farm in Franklin County near Connell, Washington, where his father was born.

The family settled in Connell, where Mark lived until graduating from high school. He worked on the family farm and every year, once the harvest was complete, they would spend time at their favorite place, Orcas Island, clamming, exploring, and spending quality time together.

He went on to graduate from Whitman College and earned a master's degree in business and finance from the Wharton School at the University of Pennsylvania. After completing his education, he moved to Spokane, Washington, and joined the securities analysis staff at Murphy Favre, Inc.

In his youth, Mark played the French horn and participated in various sports. A true bibliophile, he loved reading—particularly about English history and Henry VIII. His hobbies included archery, photography, keeping tropical fish, and collecting classical cars, including a 1970 Dodge Charger and a Porsche. He enjoyed fishing and his favorite kind of fishing was bow fishing on Kootenai Lake with a close friend.

In 1971, Mark married his beloved wife, Colleen. Over their 55 years together, they shared many adventures—riding a hot air balloon over Spokane, flying into a Hawaiian volcano caldera, exploring Orcas Island, and walking countless beaches. They enjoyed spending time at the public library, going to the Symphony, and listening to classical and jazz music. He was a devoted husband and caregiver, always creating new recipes to surprise and delight her. "A sweet, kind man," his sister said.

He is survived by his twin sister Marcia Black; nephew Donald Black; niece Kimberly Schwittay; great-nephew Maxwell Carson; stepchildren Karen Finch, Linda Reichert, and Dan Schroer; 14 step-grandchildren; and 30 step-great-grandchildren with more on the way.

Mark was preceded in death by his parents, Elisabeth and Donald; his brother, Robert Mittelstaedt; and his stepson, Richard Schroer.

In honor of Mark's love for learning and adventure, the family encourages friends and loved ones to spend time reading, spending time in nature, or cooking a favorite recipe in his memory.

A memorial service will be held Friday, July 18, 2025, at 10:00 at the Immaculate Heart Retreat Center, 6910 S. Ben Burr Rd., Spokane, WA 99224.