Leon Marsh is the brother of Arthur Marsh, they were both born in Broome County, New York. Leon was born January 1859 and married Trina (called Tina) Johnson. She was born October 1864 in Norway. Tina immigrated to the USA in 1888 and they were married in 1890. They had one son Guy Marsh.
My sources are the 1900 U. S. Census, South Dakota, Day County