Cathy Diane Helfinstine, age 63, of Willmar, Minnesota, died Sunday, March 22, 2015, in Brookings, South Dakota. Visitation will be held on Thursday, March 26, 2015, from 5:00 to 7:00 pm at Eidsness Funeral Home in Brookings. Cathy Diane (Dahl) Helfinstine was born on November 28, 1951, at Camp Atterbury, Indiana, to Merlyn (Mike) "Bud" and Jacquelyn Dahl. Her family moved to Brookings, South Dakota, where she graduated in 1970. Cathy was united in marriage to David Helfinstine on February 12, 1974, in Madison, South Dakota, where they lived until 1985 when they moved to Willmar, Minnesota. To this union two children were born, Ryan and Betsy. Cathy worked as an optician at Midwest Vision Center for over 20 years. Following her retirement, she worked for the Willmar Public Schools as a paraprofessional. Cathy's greatest joy was being with her grandchildren - it is what she loved the most! In the summer Cathy welcomed her grandchildren and friends to their swimming pool. Poolside snacks and floating toys were abundant. Her favorite vacations were anywhere with a warm beach or their getaway in the Black Hills. Cathy loved to have friends over for holidays and Halloween was a magical time at her house. Cathy is survived by her husband of 41 years, David; her son, Ryan Helfinstine (fiancée Erin); her daughter, Betsy (Adam) Staley; six grandchildren: Cole, Tucker, Koda and Tara Helfinstine and Jack and Ellie Staley. She is also survived by her sisters: Rebecca Estenson, Laurie Foerster and Tami Dahl; and many nieces, nephews, and cousins. She was preceded in death by her parents, Bud and Jacquelyn Dahl and her in-laws, Rex and Jean Helfinstine.