Maybe you can locate some more of his siblings - on https://familysearch.org/
Example below:
U S Census, 1930 Carrington, Foster, ND
Head Sherman O Hess M 28 OH
Wife Grace C Hess F 27 IA
Son Sherman Hess M 0 ND
U S Census, 1940 Ward 3, Devils Lake, Devils Lake City, Ramsey, ND
Head Sherman O Hess M 37 OH
Wife Grace Hess F 37 IA
Son Sherman Hess M 10 ND
US Census, 1930 Bull Moose, Wells, ND
Head William A Hess M 59 PA
Wife Stella P Hess F 56 OH
U S Census, 1910 Oakes Ward 1, Dickey, ND
SELF William A Hesss M 39y PA
WIFE Stella P Hess F 37 OH
DAU Velma L Hesss F12 OH
SON Ross Emery Hesss M11 OH
DAU Pearl M Hesss F10 OH
SON S Oaklyn Hesss M8 OH
DAU Mildred E Hesss F 6 OH
Parents: W. H. Hess, Estella Cretcher
Velna Lucile Hess
birth: 02 Jun 1897 Champaign county, OH
Ross E. Hess
birth: 11 Jul 1898 Champaign county, OH
Pearl Kay Hess
birth: 14 Mar 1900 Champaign county, Oh
US Census, 1930 Bull Moose, Wells, ND
Ross E Hess
spouse: Mable A Hess
child: Crystal I Hess
US Census, 1940 Election Precinct 10 North Dayton, Yamhill, OR
Ross Hess M 41 OH
Wife Mabel Hess F 31 SD
Dau Crystal Hess F 10 ND
Son Howard Hess M 8 ND
Son Richard Hess M 4 OR
Dau Shirley Hess F 0 OR
????? niece
Edna Lucille Fisher
Death Date: 02 Jul 1994 Charlotte, Mecklenburg, NC
Birth19 Mar 1942 Greenville, OH
Burial Darke County, OH Stelvideo Cemetery
Residence: Lexington, Lexington, SC
Street Address: 126-8 Sandy Springs Lane
Age 52 Divorced
Birth Date: 19 Mar 1942
Parents Edgar L. Smith Velma Louise Hess