The patronymic surname Larson is purely Scandanavian, meaning literally "son of Lars." As such, it would change with every generation, though after 1850 the custom of maintaining a permanent surname became more popular, reaching the mainstream by 1880.

Per Hazel Cecelia Johannesen (Karstens) (presented verbatim as is written):
The Hans Larson had a boy born November 2, 1854, naming him Ole Larson. He grew to young manhood and met a girl, Annie Helen Peterson, daughter of the Andrew Petersons. Annie was born September 1864. They were married and lived in the Black Hills on a ranch near Hisega, South Dakota. Ole loved to fish and took great pride in his fruit. Apples of all varieties and always lovely strawberries. Annie would make jam and sauce from them and what was left Ole would take to the store and sell. Oh yes, I forgot to mention that when we visited in the summer, we helped pick berries. The biggest ones never got in the boxes!

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Annie and Ole raised a nice family of six children: Hannah C., Addora Cecilia, Orval Earl, Oleanna Lae, Paul Lawrence, and Edna Josephine. Ole passed away Mothers Day in 1930. Annie lived 15 years and two months longer making her home with Edna most of the time, passing away in August 1945.

Addora Cecilia was born March 25, 1887. She met and married Ehard Johannesen who was born on March 17, 1884. Ehard was better known to everyone as Ed. They made their home on their homestead site northeast of Quinn, South Dakota. They raised a family of six children: Annie, Ruth, Harry Edward, Ella Marie, Esther May, and Hazel Cecelia. Ed and Addora lived a very full life. Addora passed away Oct. 1949; Ed passed away March 1953.