Barbara Eileen Gordon

Thelma Gordon is Barbara Gordon's biological mother who prior to Flashpoint continuity changes, died in a car accident.

Barbara Gordon's Origin
Thelma Gordon has had few comic appearances, mostly flashback's to times before Barbara Gordon was Batgirl/Oracle. Following Crisis on Infinite Earths, Barbara Gordon was no longer James Gordon's biological daughter, but instead his niece/adoptive daughter. Barbara's biological parents were Roger Gordon (Jame's brother) and his wife Thelma. When Barbara was young, Thelma died in a car accident, which lead to Roger succumbing to alcoholism, and Barbara living with her Uncle.

DCnU
Following the Flashpoint continuity changes to the DC Universe that brought about The New 52, Barbara mentions to her new roommate, Alysia Yeoh that instead of dying, her mother walked out on her and her father (not yet clear who her father is now.) On Christmas morning, when Barbara and Alysia are opening presents, the doorbell rings, and Barbara finds her mother waiting for her outside.