Mark William Siepker

October 28, 1954 – May 6, 2026

Mark Siepker, age 71, passed away on May 6, 2026, in Omaha, NE. Born in Carroll, IA, Mark was the eldest child of Ray and Marlene (Renze) Siepker. He was preceded in death by his beloved wife Becky Jo (Bumann) and his father Ray. Mark is survived by sons Andy (wife Jennifer, grandchildren Sophia, Andrew Jr, Theodore, William); Jeffery; Bret (wife Jordan, grandchildren Rowan, Sloane); his mother Marlene; siblings Jeff Siepker (Connie), Joni Kienast (Tim), Renee Halbur (Randy), Julie Fogleman (Steve); and partner Anita Jeck.

Mark retired as an accountant for the city of Bellevue in 2018 to care for wife Becky and son Jeff. Previous work included First Data Corp and Northern Natural Gas. He was an avid bicyclist and a frequent participant in rides across Iowa (RAGBRI) and Minnesota (TRAM). In 2009, Mark and son Jeff rode a specialized tandem bike nearly 300 miles to raise funds for the Ollie Webb Center, whose mission is to enrich the lives of people with developmental disabilities. Mark was the first Humanist Celebrant in Nebraska and a beloved member of Second Unitarian Church of Omaha.

A Celebration of Life will be held on June 5 at 6:30 pm at the First Unitarian Church of Omaha at 3114 Harney Street. Attendees are invited to honor Mark by wearing a splash of color as he favored bright colors.

Suggested memorials include Mosaic in Omaha (serving people with disabilities), Ollie Webb Center, Alzheimer’s Association, American Cancer Society, and Second Unitarian Church Endowment Fund.