Abraham Simpson

Abraham Jay-Jedediah "Abe" Simpson, known as Grampa Simpson, is a character in the animated television series "The Simpsons". He is voiced by Dan Castellaneta. He first appeared on The Tracey Ullman Show in the Simpson Short "Good Night".
Role in the Simpsons.
Family.
He is the father of Homer Simpson and the grandfather of Bart, Lisa and Maggie; he is the husband of Mona Simpson, but later he also has been married for a short time to Amber (a woman that Homer married in Las Vegas too) and to Selma Bouvier, now he's married to Rita LaFleur. He lives in an old folk's home.
Characteristics.
Abe Simpson is a World War II veteran and he often tells long, unlikely and rambling stories about his past. He was married to Mona Simpson for many years until she became a fugitive after she destroyed biological weapons owned by Mr. Burns.
Grampa Simpson has a poor relationship with his son Homer.