I may have posted this elsewhere, but there were death notices for Henry Gielens (survived by Therese Wellinghoff Gielens) in the local German language newspapers.
"Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
For more specific information contact:
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007... helping to access our historic German-American culture.