Mary D. Pekas, age 88, passed away peacefully on January 30, 2026 in Sioux Falls, SD. Visitation will be held at Geise Funeral Chapel in Estelline, South Dakota, from 9:00 a.m. until the memorial service, which begins at 10:00 a.m., on Saturday, February 7, 2026. A Private Family Burial will follow at the Trinity Lutheran Church Cemetery overlooking Lake Mary.

Mary Knutson was born August 5, 1937 in Max, ND to Odin and Martha Knutson. She graduated from Sacred Heart Academy, Minot, ND in 1955 and from Mount Marty College with Bachelor of Arts in 1974.

She was married in 1958 to Jack Pekas, having four children: Lori Eckholt and Jeff (Denise) Pekas of Yankton, SD, Mark Pekas of Sioux Falls and Carolyn (John) Goodson of Stuart, FL. She had seven grandchildren and five great-grandchildren.

She had an in-home daycare in the 60’s with up to 13 children, creating fun-filled lifelong memories. She worked for Welcome Wagon in Yankton, often recruiting her young children to help assemble packets and set up banquets to welcome new families to town.

She worked as Regional Sales Manager and Instructor with Dale Carnegie, was Director of Admissions at Nettleton College and Placement Director at Boyles VanSant Business College.

She founded Telemarketing Institute, Inc. in 1982 and was known for consulting, training, lead generation and sales for over 40 years with national, international and Fortune 500 clients. She operated a virtual call center in the early 90s, employing subcontractors working remotely from their rural homes.

She was a board member of Teleprofessional Managers Association, a speaker with the National Speakers Association and a Certified Marketing Executive with Sales and Marketing Executives.

She was author of telemarketing and sales books, some of which were taught in high schools and colleges. In her eighties, she and her friend Dr. Nancy Zare published No Pressure Selling and audio book Stop Selling, Start Relating.

She lived for decades on the shores of Lake Poinsett, enjoying her garden, and watching ducks, geese and pelicans, often with her friend and business associate Muriel Jamison. Her love for animals endured for a lifetime, especially her occasional cat.

She met Morrell Spencer in 2000, sharing life and experiences together for 22 years. She loved to travel, whether for business or pleasure, and visited all 50 states and all seven continents in her lifetime. She wintered in Stuart, FL for many years close to her daughter Carolyn and her family.

She had a heart for faith, family, friends and fun. She was a bright light, a welcome smile and a force for positivity and overcoming obstacles, even declaring the words "can't" and “impossible” as dirty words for her children growing up.

She was preceded in death by her parents and her sister Irene Harmer.

In lieu of flowers, memorials may be sent to the Bethany Lutheran Foundation in Mary's name.   https://mybethanyhome.org/foundation