"We are truly saddened by the passing of Mary Thomas," FIU Athletics Director Pete Garcia said in a statement on the school's Web site Thursday. "The Thomas family is in our thoughts and prayers during this time of mourning. I know how much she meant to Isiah and the entire Thomas family. Our hearts go out to Coach Thomas and his family."
Hashim Alaudeen, Florida International director of men's basketball, said Thomas has returned to Chicago.
The Chicago Tribune reported she died of natural causes Wednesday, ending a life that was honored with the 1989 TV movie "A Mother's Courage: The Mary Thomas Story."
The NBC film featured actress Alfre Woodard as Thomas and detailed Thomas's struggles as a single parent in Chicago.
Among the film's moments was a depiction of how Thomas threatened gang members with a shotgun after they attempted to recruit a young Isiah Thomas and his brothers.
Isiah Thomas found great success with the Detroit Pistons, leading his team to the NBA championships on two occasions. He was elected to the basketball Hall of Fame and was voted one of the NBA's 50 greatest players.
After his NBA career ended in 1994, Thomas coached the Indiana Pacers for a few seasons before serving as the president of basketball operations for the New York Knicks.