Susan Kay Thornton (nee Sweigard) was born in a blizzard on Christmas day in 1944 in Sycamore, Ohio to R. Marie Sweigard (nee Case) and Vernon W. Sweigard.  She was raised on the family farm, where she enjoyed drinking fresh, warm milk every morning straight from the cows, ice-skating on the local pond with neighbors and friends, and family gatherings filled with hayrides, card-playing, and making home-made ice-cream. 

She attended the local school in Sycamore, where K-12 was housed in one building, and subsequent to graduating high school in 1963, went on to earn her degree in elementary education from Heidelberg University in Tiffin, Ohio in 1967.   She moved to Warren, Michigan for her first teaching job, and met her future husband, Duane A. Thornton at a St. Patrick’s Day Dance at the local army base in 1968.  On July 27, 1968, she and Duane were married and became loving partners, best friends, and playmates for more than 57 years.   

Susan taught school in Michigan and Wisconsin and spent many years as a fourth-grade teacher at Eagleville Elementary School in the Mukwonago School District.  Her favorite aspect of teaching was observing and supporting her pupil’s learning and development, particularly in the foundational subjects of reading, writing, and arithmetic.  She completed her master’s degree in Reading Education from the University of Wisconsin-Whitewater in 1985 and put great effort into continually improving her skills as an educator throughout her career.

She was a loving and dedicated mother to children Kimberly Sue Thornton (Gunther Koppelhuber) of Vienna, Austria, and Kevin Colby Thornton of Hudson, Wisconsin, and a blessed grandmother to Marie Kay Koppelhuber and Koloman Josef Koppelhuber, with whom she shared and encouraged an interest in playing piano and reading. 

The family moved to Mukwonago in 1974, and Susan spent many years in service to her community and church. She was a member of the Mukwonago Jaycettes and served as an organist both at her home church in Sycamore, Ohio and later at Vernon Lutheran Church and Mt. Olive Lutheran Church in Mukwonago.  She was a valued member of the Church Council and Praise Team at Mt. Olive, a member of the ladies’ book club, and of the Knotty Knitters Knitting group.    Her faith was the bedrock of her life.   

Following retirement, she discovered an appreciation for long-distance travel, engaging in many trips throughout Europe and the British Isles with Duane, learning about new places, perspectives, and people.  In recent years, she was content spending balmy summer evenings on her deck with Duane and Charlie, her Cavalier King Charles, simply enjoying the serenity of the area along Jericho Creek.

Susan passed away peacefully at home on February 27, 2026, surrounded by her husband, children, and grandchildren after facing cancer with strength, courage and grace.

She is also survived by her cherished Ohio cousins and a wide network of kind and supportive friends, with whom she made many beautiful memories during her lifetime.

Her family would like to extend special appreciation and thanks to the Oncology Team and the Home-Hospice Care Team from Pro-Health Care.

Visitation will be held on Thursday, March 5, 2026, at Mt. Olive Lutheran Church in Mukwonago (211 Main Street) at 10AM followed by a funeral service at Noon. 

In lieu of flowers, memorial donations may be made to Mt. Olive Lutheran Church https://mountolive-elca.net, or to the charity of your choice.