Update:

I have obtained the death certificate and obituaries for Theodore Karls. He was born October 21 1850 in Germany, and immigrated to Wisconsin when he was a small boy. He had two brothers named Nicholas and Bernard who eventually moved on to Antelope, Sheridan County, Montana, and at least one sister who moved to Canada and was married to a Weber. Theodore died October 4, 1916 in Fond du Lac, WI, and is buried in Calvary Cemetery there.

If anyone has any information on his brothers Nicholas and Bernard in Montana, please reply or contact me.