That's great. I was up in Big Stone Gap just this past May and interviewed a serpent handler named Bill Pelfrey, the son of Oscar Pelfrey, who died of a serpent bite at Big Stone Gap back in 1968.
I see that you've gotten in touch with my friend Ralph Hood. He's worked a good deal with Jimmy Morrow who probably has more information on your grandmother.
Whatever you find out from your mom and aunts, be sure to pass it along. My regular email is: firstname.lastname@example.org
Keep in touch.