Kathleen Lass Wacker was born in Longmont in 1940 to Paul Wilhelm Lass and Caroline Agnes née Sweeney. She graduated from Longmont High School and earned an associate degree in home economics from Colorado State University.

Kathleen met Daniel C. Wacker, Jr., in 1955 on a blind date arranged by a mutual friend and married in 1961 while Dan was serving in the Air Force. Partners in life, they lived in Orlando, Florida, where son, Paul, was born, and San Bruno, California, where daughter Kelly was born, before returning to their beloved home state of Colorado. They resided first in Berthoud where they were members of the Whipple Club and the Northern Colorado Draft Horse Association. One of her favorite memories was spending a wedding anniversary side-by-side on the seat of a Belgian horse-drawn manure spreader. She said stirring up "stuff" (not the actual word she used) was a great way to celebrate. In 1996, they relocated to a farm north of Fort Morgan where she brought color to the Plains with cheerful flower plantings around the house and front gate. She was proud to participate in the Morgan County Barn Quilt project.

For most of Kathleen's working life she was a bank teller employed by Wells Fargo in California, Berthoud National Bank, and Farmer's State Bank in Brush where she ran the drive-up window. She loved the personal interaction with her community and enjoyed getting to know her customers over the years.

Kathleen was well known for her robust sense of humor and sometimes mischievous nature. She was a stalwart spouse and caring mother whom her children's friends lovingly called "Mama Wack." She enjoyed going for scenic drives, especially in the mountains—the narrower and curvier the roads, the better—and she loved picnics by the St. Vrain River and Big Thompson River.

She enjoyed horseback riding with her husband in their younger years. A friend to animals, she had so many cats and dogs it would be difficult to give all of them credit for being her companions, although George, a husky orange tabby, was a particular favorite. In recent years, she took great pleasure in observing the many wild birds that came to their well-stocked feeders.

Kathleen passed peacefully on Thursday, March 13, 2025, with family members present. She was preceded in death by her parents and sister, Marilyn Toole, and is survived by husband Dan, children Paul and Kelly, daughters-in-law Karla and Amy, sister-in-law Darlene, and grandchildren, Geoff and Kurt.

At her request, no memorial service will be held. Her family asks that you honor her memory by spending time with loved ones enjoying good stories and lots of laughter with a favorite hot or cold drink in hand.