Annette Birkin
Annette Birkin was the wife of William Birkin and the mother of Sherry Birkin. Annette assisted her husband in his work with the G-Virus, which they conducted together in the underground labs beneath Raccoon City. Fiercely loyal to her husband's work, Annette held onto one of the few remaining samples of the G-Virus after William became mutated as a result of an attack by the Cleaners. Despite being a terrible mother who neglected her daughter, she called Sherry shortly after the accident and told her to go to the RPD, where, Annette hoped, she'd be safe.
Annette ended up being one of the only researchers inside the underground labs to avoid becoming infected with the T-Virus, and she did so by staying mobile and avoiding mutants and zombies alike. During one stroll through the sewers Annette encountered, by chance, Leon S. Kennedy and Ada Wong. She shot Leon, then, holding Ada at gunpoint, told her how William had become mutated, and all about the G-Virus, planning to shoot Ada anyway. But when she moved to do so, Ada reacted quickly and knocked Annette over a railing and into a deep pool of water.
Although Annette survived, she was badly injured. Found by Claire Redfield, she was aghast to learn that Sherry hadn't remained at the police station. She then limped her way back to the underground labs, where she cornered Leon and taunted him by revealing that Ada was not who she claimed to be. When Ada set the facility's self-destruct sequence into action, Annette was crushed beneath falling debris. Again, she survived, and followed Leon to the main shaft of the facility. There, she came upon him and Ada, and shot Ada, presumably killing her before finally collapsing from her own fatal injuries. Moments later, Sherry and Claire arrived, and Annette had one last tearful good-bye with her daughter, apologizing for being such a neglectful mother, before she finally expired.