Can anyone help me find Robert M Shelton father?

Great grandfather
Robert M Shelton married Cora Chisholm (Cora married a second time)
Robert was born Oct 1888-27 Dec 1959 in Jefferson County, Kentucky
Cora was born May 1889 in Kentucky (found no death record)

Robert and Cora Shelton children were:
Juanita Born 01 Jan 1905 in Jefferson County, Kentucky
Robert William "Tom" Shelton Born: 19 Nov 1906
Died 16 April in Louisville, Jefferson, Kentucky
Emma Shelton was born 1909 in Jefferson, Kentucky
Louise H Shelton was born 13 Aug 1911 in Jefferson Kentucky

grandfather:
Robert William "Tom" Shelton (1888-1959)
Thelma Wilkerson

Father:David Eugene Shelton
09 June 1952
Died 07 Sept 2012