Mark Allen Olson

Mark Allen Olson, age 66, of Roscoe, Illinois passed away at home on April15, 2025.

Mark was born on April 5, 1959, in Earlville, Illinois, the son of Paul Olson and Joyce (Weaver) Olson. Mark grew up in Prophetstown and graduated from Polo High School. He went on to earn his Bachelor of Science in Biology from Illinois Wesleyan University and his Master of Business Administration from Northern Illinois University.

Mark married Ellen K. (Reese) Olson on November 21, 1992, at the Cherry Valley United Methodist Church in Cherry Valley, Illinois and together they raised two sons, Matthew and Andrew. Mark loved his family, supporting his sons in their journey to adulthood and being there for school, scouts, school band or moving from one state to another.

Mark worked for OSF Saint Anthony in the laboratory as a Clinical Lab Scientist MT(ASCP) for 37 years. He enjoyed being a preceptor to Medical Laboratory Services students as they were beginning their careers.

Mark was also deeply involved in Scouting, where he served as the Committee Chair and a Den Leader for Cub Scout Pack 620/6202 for over 20 years. Mark also simultaneously served as Scoutmaster for Troop 622/6222 for over 15 years. As Scoutmaster he helped to lead not only his sons to achieve the rank of Eagle Scout, but also numerous other boys under his guidance. Mark had a passion to be a mentor and friend to scouts wherever they were along their journey.

Mark enjoyed camping, committing to spending one week every summer with the troop, and always looked forward to the weekend campouts. Mark was proud of his Dutch oven cooking over coals, often experimenting on his family before subjecting his scouts to his cuisine. Popular cuisine included Dutch oven pizza and cobbler. Mark enjoyed the outdoors, whether it was hiking, birdwatching, or gardening. Mark also cherished our six cats (aka the “six pack”) Jayme, Lucy, Gunner, Myles, Chester and Otis, all of which he spoiled rotten.

Mark is survived by his wife, Ellen, sons Matthew and Andrew, three brothers, Dave, John and Steve (LeAnne), as well as many nieces, nephews and cousins.

A Celebration of Life will be held on Saturday, April 26, 2025, from 1:00pm to 3:00pm at the Roscoe United Methodist Church, Harmon Hall in Roscoe, IL.

In lieu of flowers, memorial donations may be made to the family for a memorial to be determined at a later date.