The only Hiram STRAUB in the 1930 census is in Schuylkill Co., PA, and there are no STRAUBs, at all, in the 1930 census of Franklin Co., KY.(The 1940 census has not been released.)I also don't find Hiram in the SSDI (Social Security Death Index).
If you know where and approximately when Hiram died, I would recommend getting a copy of his death certificate from the county where he died, which should tell you when and where he was born and the identity and birthplaces of his parents.
In the 1900 census, there are ten Mary STRAUBs born 1881-83, but none born in or living in Kentucky.Can you tell me, please, where Mary STRAUB was born, her married name, and where she died?
If you can't get Hiram's death certificate, getting Mary's would be almost as helpful.