Jeffrey A. Armstrong

It is with great sadness that we announce the passing of our beloved Jeffrey Allan Armstrong, who departed from this world on July 27th, 2025. While our hearts are heavy, we find comfort in honoring a life well-lived with love, laughter and cherished memories.

Jeffrey Allan Armstrong was born March 1, 1947, in Duluth, Minnesota, to William and Margaret Armstrong. He attended school in Duluth, Minnesota. Following his schooling, life led him to California to start a family.

Eventually, he and his young family returned to Minnesota - where he started the first of many business adventures - namely so - Jeff's Texaco.

On December 22, 1979, he married the person that would become truly - his person, his best friend and the one that would make sure he was taken care of always - Sandra (Sandy) Jean. During their lives together ,they lived in Lincoln, Nebraska for a short time where they came up with the idea to start a business, returning to Sioux Falls to do so. He would always share, proudly - that they borrowed the money to start it and made enough money that they had the loan paid off within the first two weeks of operation. And although they didn't have children together, the business they created was their "BABY - aka Splash City" -  which turned into a life long undertaking - allowing them to provide for their combined family of four girls. After "retiring" he was finally able to relax and take it easy - he even managed to join Facebook - or as he called it "book face".

Jeff was a member of Eastside Lutheran Church, where for a time he served on the church board. He and Sandy were also-former, long-time members of the Sioux Falls Corvette Club (they especially loved going to the rallies and auto-crossing) - where they made many life- long friends.

Jeff was a loving - albeit stern father, grandfather, caring friend and devoted husband, his wife, Sandy, never had to pump her own gas - he would even drive to where she was to take her car to fill it up - and his children knew that he always had their backs and that they could come to him with anything - without hesitation or judgment. He had several friends that he talked to on the regular - all of which would take his calls at all times of day or night - even when they were on completely different time zones (Jim McClure especially was a gem) to talk recipes, life or to just listen.

Jeff and Sandra enjoyed traveling - especially doing so via a Royal Caribbean cruise ship. During the winter months, Jeff could not wait to get to their place in Naples - to relax and float in the pool and hang out with great friends - aka his happy place. They absolutely, loved their Tuesday night dinner outings with their much loved dinner club, it gave them something to look forward to every week.

Grateful for having shared his life are his wife, Sandra Armstrong of Sioux Falls; daughters, Lisa (John) Shepherd, Henderson, NV, Kelli (Lon) Levenhagen, Sioux Falls, and Kerri Keogh, Sioux Falls; 5 grandchildren, Sierra (Connor Bradley) Shepherd, Jordan Armstrong Henderson, NV, Landon Levenhagen, Sioux Falls, Kaylee (Keegan) Van Egdom, Minneapolis, MN and Griffin Keogh, Sioux Falls; his sister, Kim (Philip) Allen of Sioux Falls; and many nieces and nephews.

He was preceded in death by his parents, his brother, Sheldon; a daughter, Lora Mendoza; and many other aunts, uncles and cousins.