Have you collected the family death notices for Peter Chapek / Chapeck (referencing Maria) from either of two of Milwaukee's German newspapers? There are also notices found in three different German newspapers for a Maria Chapek.
These are indexed in the collection: "Milwaukee's German Newspapers; an index of death notices and related items", covering 1844-1950.
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007... helping to access our historic German-American culture.