Karen Siewert

Karen (Horton) Siewert, age 83, of Markesan, passed away on August 3rd, 2026, surrounded by loved ones at ThedaCare Regional Medical Center in Neenah, WI. 

Born on July 8th, 1943, in Portage, WI, Karen was the daughter of Arden and Thelma (Oosterhoff) Horton. She graduated from Cambria High School in 1961. Karen lived a life marked by devotion to her family and friends, dedication, kindness, and quiet strength.

Karen caught the attention of the love of her life, Dennis Siewert, in unforgettable fashion—by performing a behind‑the‑back trick pool shot at a local tavern. She always called that place the Greasy Spoon. They were married on March 29th, 1963, at First United Presbyterian Church in Cambria, WI. Shortly after their wedding, they took over Dennis’s family farm on Mackford Prairie, where they began raising their family and building a life rooted in hard work, partnership, and love.

Throughout her life, Karen held various jobs, but her greatest passion was raising her family. On the farm, she was the head milker and the backbone of both the farm and the household. Between milkings, she shuttled Dennis to the fields, ran errands, raised the children, and kept everyone well fed. Her steady presence and tireless commitment shaped the rhythm of daily life and created a home filled with warmth and care.

In her free time, Karen enjoyed reading, knitting afghans, doing word search puzzles, bowling, and playing Euchre with her sisters and her mom. She had a lifelong green thumb—able to revive any struggling plant—and her home was always filled with thriving greenery. Karen loved small dogs and always shared her lap with them, finding comfort and companionship in their presence. She also cared for pet birds over the years, including Charlie, with whom she chatted daily. Karen cherished watching the wildlife on the farm, especially the deer and the many varieties of birds that visited her well‑stocked feeders.

Karen is survived by her two daughters, Denise (Lora) Siewert of Apple Valley, MN, and Sheryl (Kelly) Immel of Fond du Lac; three grandchildren: Brooke (Kyle) Siewert of Waupun, Matthew Immel of Fond du Lac, and Sydney (Tanner) Immel of San Diego, CA; one great‑grandchild, Evelyn Krueziger of Waupun; two sisters: Gloria (Jack) Slinger of Cambria and Rita (Duane) Burmania of Cambria; isster-in-law Mary (Robert) Brooks of Madison; and many in‑laws, nieces, nephews, extended family, and friends.

She was preceded in death by her parents; her husband, Dennis; two sons, Jeffrey Siewert and Michael Siewert; and two brothers, Edward Horton and Thomas Horton.

Karen will be remembered for her unwavering devotion to her family, her gentle humor, her resilience, and her ability to nurture life—whether in her children, her plants, her beloved pets, or the wildlife she loved to watch.

Visitation for Karen will take place on Saturday, August 8, 2026 at Werner Harmsen Funeral Home in Waupun from 9:00 a.m. until the time of the funeral service at 11:00 a.m. Burial will take place at Mackford Union Cemetery. In honoring Karen, family and friends are encouraged to dress casually and wear something purple, her favorite color.