Tabitha Galavan is the sister of Theo Galavan.
Breaking inmates out of ArkhamEdit
Tabitha broke into Arkham Asylum to break six inmates out, killing several guards while doing so. Later at a penthouse, Tabitha's brother, Theo, introduced himself and her to the kidnapped inmates, offering them the chance to become a team of brilliant outlaws, that would make Gotham City tremble. After Richard Sionsis refused, becoming jealous that Theo touched Barbara, Tabitha killed Sionis on the orders of Theo.