There were obits. with photos for Oswald Jaeger in Milwaukee's German language newspapers. It's possible there were death notices or obits. his parents for Franz (d. 1886?) and Helene too. There are about 500 occurrences of Jaeger and Jäger indexed in the growing resource "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 immigrant culture.