Sylvia McFly (née Misken) is a minor character in the back to the Future franchise, appearing in Back to the Future: The Game - Episode 2: Get Tannen!
She was the mother of George McFly and therefore, Marty's paternal grandmother, who wad extremely close to him.
History[]
Background[]
Sylvia was born in 1903. In 1931, she later married Arthur McFly and had a son with him, George.
In 1955, Sylvia and George were on there own.
By 1985, she had been a grandmother two three grandchildren, David, Linda and Marty, The latter of whom she was close with
Back to the Future Novelization[]
According to the novelization, when Marty time travel from 1985 to 1955 did not want to go over to his father's house in fear of running into her and terribly frightened Sylvia even though he wasn't born yet.
Back to the Future: The Game[]
In the 1930s, Marty and Emmett Brown attempted to get Arthur together with Sylvia, though they were unclear as to who she was then.