All of your evidence points to my grandfather, John Henry Duval. His mother Laura, after the death of his father, Alfred/"Fred", married a Mr. Wilson. The 1930 census puts them in Ouachita with Lillie and Mr.Wilson's son by another marriage. My grandfather, John Henry, b. 1916, married my grandmother, Nellie Pearl Dozier in Monroe, Louisiana. My mother, Olive Ann Duval, b. 1938, married Truman Earl Blair of Fort Worth, Texas in the year 1955.
I have no other information about Alfred's son, John Henry. My grandmother and he divorced and my mother never knew him. She only knew of Lillie through her mother, Pearl.
I hope this helps a little. Regards, Anita Ann Blair Blackwell