A search for "John E. Douglas" on Ancestry.com shows cross-listings for John ROSENBERG, including a 1920 federal census listing in Milwaukee (at age 2), with parents John W. Rosenberg (age 25) and Olive E. Rosenberg (age 24). His birth year is reported as 1917/1918.
The cross-listings include the Social Security Death Index and Kentucky Death Index entries for John DOUGLAS (1917-1977).
By 1930, he was listed in the census in Grand Chute, Outagamie County, WI with parents John and Olive ("Oline") Rosenberg and younger siblings Warren, Ruth, and Dorothy.
Elsewhere online, there was a 1949 high school alumni listing for Wittenberg (Shawano County) WI for Olive YOUNG, Class of 1912, who is shown as "Mrs. John Rosenberg," 226 South Drew St., Appleton, WI.
An article in the Appleton Post-Crescent (24 June 1939) indicates that the city council authorized the city engineer "to hire John Rosenberg and Harry Jackson to make the preliminary survey of the proposed high-level bridge." Per one of the earlier census listings, John (Sr.) was also an engineer, so it's not entirely clear if this article is making reference to the father or the son.
All of this came from a rather quick search, so it's likely that much more information can be uncovered with the Rosenberg name in mind.
I hope this helps point you in a productive direction!