I couldn't find any marriage for Louis Hof and Louise Williams in the Illinois Statewide Marriage Index.But I did find Louis Hof in the 1900 census.
Cook Co, Roll 283, Book 1, 30th Ward, p. 138 They lived at 6134 Morgan Ave (that's what it looks like, really couldn't make the street name out).They appear on lines 30, 31, and 32 on p. 138.Louis came to the U.S. in 1888, it says.
Hof, Louis, head, age 28, born Dec 1871, married 4 years, born in Germany, his parents also born in Germany.
Hof, Louise, wife, age 22, born Jul 1877, l child born, l child living, born in Illinois, parents both born in Germany.
Hof, Anna, daughter, age 3, born Jun 1896 in Illinois, father born in Germany, mother born in Illinois.
Louis' occupation is listed as labor, and he rents his own home.