Traverse City, Michigan - Mary DeDecker VanderKolk passed away unexpectedly at her home on January 1, 2026, at the age of 74.

Mary was born on February 7, 1951, in Warren, Michigan, to Frank and Jean (née Halmich) DeDecker. She was the eldest of nine children and came from a long line of strong women. She attended St. Anne's Catholic School and graduated from Warren High School in 1969. From an early age, Mary's compassion and drive were evident, qualities that would define both her personal life and her remarkable career in nursing and education.

Mary earned her Bachelor of Science in Nursing from Michigan State University, where she met her husband of 48 years, Dr. Michael VanderKolk, who she married on June 18, 1977. She began her nursing career at Sparrow Health System before the couple moved to Ann Arbor. There, Mary worked as an ICU nurse at St. Joseph's Mercy Hospital while earning her Master's degree in Nursing from Wayne State University in 1980.

In 1984, Mary and Mike moved to Traverse City, where they raised their four children—Lauren, Chris, Nikki, and Allison. She balanced a full career while Mike worked long, unpredictable hours as a general surgeon. She carried the load at home and still pushed forward professionally. Her drive, resilience, and ambition made her a true trailblazer including when she earned her MBA from LSSU in 1992. Starting as an ICU nurse at Munson Medical Center, she soon began a 32 year long career as a nursing instructor at Northwestern Michigan College until her retirement in 2017. She helped train many nurses in our community over those years.

Mary's dedication to nursing extended beyond the classroom and bedside. She served for 8 years on the State Board of Nursing in Lansing from 2012-2020, contributing her wisdom and advocacy to the profession she loved. Even in retirement, Mary answered the call to serve, returning during the COVID-19 pandemic to assist with vaccine clinics at Munson Kalkaska.

Above all, Mary cherished her family. She delighted in spoiling her loved ones, especially her grandchildren—Axel, Lana, Basil, Wilder, Ellie, Lindsey, Lillian, Ryker, Hadley, and Aurora—and treasured time spent together. She found joy in simple pleasures: playing FreeCell, reading, sipping Diet Coke, relaxing at White Birch Lodge, and traveling with Mike, especially their cherished annual trips to Mexico. Her warmth, generosity, and quiet strength were constants to those who knew her.

Mary was preceded in death by her parents, Frank and Jean DeDecker. She is survived by her beloved husband, Dr. Michael VanderKolk; her children Lauren (Doug) Holst, Chris (Ralph Hardesty) VanderKolk, Nikki (Matt Rine) VanderKolk-Rine, and Allison (Charles) Shuff; her grandchildren; her siblings Terry (Vince Dattolo) DeDecker, Anne Hay, Gretchen DeDecker, Mark (Ingrid) DeDecker, Suzanne (Pete) Kane, John (Michele) DeDecker, Catherine (Geoff Graber) DeDecker, and Mike (Sue) DeDecker; and many nieces and nephews. She is also survived by her close friends, Sandy and Greg Somers.

Mary will be remembered for her devotion to her family, her lifelong commitment to nursing and education, and the kindness and care she extended to everyone around her. Her legacy lives on in the many lives she touched, taught, and loved.

Please recall a fond memory of Mary or say a prayer, and if so inclined, she would have appreciated a donation in her name to NMC's Nursing program.

Details for a celebration of life will be shared at a later date.

Please visit www.lifestorytc.com to share your thoughts and more.