"There is a detailed golden wedding anniversary article for John & Catharine Kastler Becker in the 18 Apr 1893 edition of "Der Seebote"."
That's a German language newspaper that was published in Milwaukee. There were also death notices and a photo in the German papers for this Johann Becker. (I'm also responding to your email message.)
"Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007 ...