Marva Cooper was Earl Cooper's daughter.
Marva and Earl shared a strong relationship. He allowed her to help him with maintenance on the Batmobile. Marva showed excellent technical skills on par with her father, as well as a great sense of loyalty to Batman. When the Penguin found their secret workshop, she was held hostage in order to force Earl to cooperate with his plan to turn the Batmobile into a booby trap. Marva showed no fear towards the Penguin as he kidnapped her and took control of the Batmobile. After the situation with the Penguin was resolved, Marva helped her father pack up their workshop and move to their new location wherein she continued to assist him.