Yuma Simpson (née Hickman), or Great Grandma Simpson (1880-1980) is Homer's paternal grandmother from "The Old Country", which has similar characteristics to Ireland or Scotland. Grampa said "Back in the old country, I don't remember which one..." Yuma was the daughter of Willard Hickman and Theodora Hutshing married Orville Simpson in the early 1900's. For a few years, they lived inside the Statue of Liberty, along with their sons, until the head of it was filled with too much garbage. With their sons they moved to Springfield where she had another and eventually died there. Yuma passed away when Marge was pregnant to Bart and long after her husband. She died around 1980.
Yuma Hickman living in the statue of Liberty calling to Abe.