Dr. Ralph Gremillion was born and raised in Alexandria, Louisiana.  He moved with his family to Thibodaux in 1969 to become a professor at Nicholls State University.  Mayor Gremillion has been married to his wife Ann for 55 years.  They have 4 children, Dr. Scott Gremillion of Alexandria, Laura Kingston of Lafayette and Allison Thompson and Mary Ann Caillouet of Thibodaux.  They have 11 grandchildren.

Mayor Gremillion belongs to a group originally called the Bi-Focal's but was recently change to The Romeo's (Retired Old Men Eating Out).