Found a Franklin Gunther b. abt 1918 in 1930 Kings Co. census, in 1920 he is listed as Franklin C. Gunther. Parents are Walter and Viola Gunther.
Found this in the U.S. Army Enlistment Records 1939-1946 at Ancestry.com:
Name: Franklin C Gunther Birth Year: 1918 Race: White, citizen (White) Nativity State or Country: New York State: New York County or City: Kings Enlistment Date: 12 Jan 1942 Enlistment State: New York Enlistment City: Camp Upton Yaphank Branch: Branch Immaterial - Warrant Officers, USA Branch Code: Branch Immaterial - Warrant Officers, USA Grade: Private Grade Code: Private Term of Enlistment: Enlistment for the duration of the War or other emergency, plus six months, subject to the discretion of the President or otherwise according to law Component: Selectees (Enlisted Men) Source: Civil Life Education: 1 year of college Civil Occupation: Linotype Operator Marital Status: Single, without dependents Height: 67 Weight: 120
I don’t find any Gunther that could be identified as Franklin on any of Ancestry’s online WWII casualty lists or war dead lists or Americans interred overseas.
I find Walter William Gunther b. June 28, 1893 filled out a WWI Draft Card and a WWII Draft Card both times living in Brooklyn, Kings Co. NY. On the WWII card ask for the name of the person that would always know your address and the name Patrica Fitzgerald living at his same address is filled in. Walter Sr is listed in the SSA death index d. Aug 1963. Son (& bro to Franklin) Walter W. Gunther Jr. is listed in SSA death index d. Dec. 12, 1997, living in Fords, Middlesex Co. NJ. I find a Frank Gunther b. March 15, 1918 died Jan 1980 card issued in NY living in Queens NY. Could be your parents were divorced and that is why the above enlistment has noted single and your mother didn’t talk about him. I would look for an obituary for the above people and order the original Social Security Application of the Frank Gunther that died 1980 to see if parents are Walter Gunther and Viola Charlock(?).