MY Great Grandfather was named John Yancy

Matthew Yancy is my nephew.. where hes researching for school I'm doing a family tree...I'm not sure whom my GGrandfather John Yancy was married to.. but I know he had a son Named Lester Alan Yancy.. whom married Francis Atzenhoefer had four sons.. Lowell Yancy, Alan Lester Yancy my father/ married my mother Mary Jane Fees..Roger Yancy, and Timothy Yancy, and a Daughter Elaine Yancy.. from Iowa, Des moines area.. I'm looking for John Yancy my great father.. whom died and was buried in Texas around the montgomery area his parents..etc...I don't have much info beings my father wasn't big on keeping in contact after he and my mother divorced,
any info would be helpful I do beleived he passed on around 1980-1990's some time at abot 90 somethang years of age...I do beleive his brothers name was Levi Yancy...
thanks for any help