|Appearance(s):||Grand Theft Auto: Vice City Stories|
|Full name:||Mary-Beth Williams|
|Date of birth:||1984|
|Place of birth:||Vice City|
|Home:||Little Havana, Vice City|
|Family:||Louise Cassidy-Williams (mother/deceased)|
Marty Jay Williams (father/deceased)
Mary-Jo Cassidy (aunt/legal guardian)
Phil Cassidy (uncle)
Mr. Cassidy (grandfather)
She is orphaned after her father is killed by Victor Vance and her mother dies from wounds caused by Armando Mendez. Whilst dying, Louise asks Vic to make sure Mary-Jo takes care of her, so it is assumed that she becomes Mary-Beth's legal guardian.
- Mary-Beth Williams is the youngest character to be featured in the Grand Theft Auto series, as well as being one of the only two minors in the franchise, the other one being Jill Von Crastenburg from Grand Theft Auto IV.