realize your query was some while back, however I am just now
trying to locate Duncan history. The grandmother I lived with:
Mary V. Williams (Ryan)was the grandaughter of Marion B. Duncan and Permelia Ann Jefferies. Their daughter, "Lizzie"
Teriza Elizabeth Duncan (Williams) was her mother.

Lizzie married William Jefferson Davis Williams in SC in the home of her Mother. This was my great grandfather with whom
I lived until his death, at which time I was eleven years old.
I only knew of them living where I reside, Birmingham, Al, but have not researched enough to find out when they moved to Alabama.
Barbara Edmonson,thedmonsons@yahoo.com