We've been searching for history on him as well. Not much is known, and I had left off researching him for a while. Maybe time to start back up again.
Anyway, I know Wilhelmine and Gordon were living at 1052 Albion Avenue, Chicago, Cook County, Illinois, in 1940 according to that year's Federal Census. In the 1930 census, they are living on Avon West Rush Road, in Rush Township, Monroe County, New York. I have copies I can email you if you want them.
Gordon may have served in the U.S. Navy during the Korean War, but I haven't been able to confirm this. I haven't searched Gerdt's website in a while to see if anything new was posted.
Searching some other databases, he may have married Charlotte Jane Nelson on October 1, 1953, in Cook County, IL and divorced on November 10, 1977, in Miami-Dade County, FL. Again, I have not been able to firmly confirm this information, they are just leads that I was following up on.
Sorry to not be more help. We are looking through my grandfather's photo albums to see if there are any photos.