Gero had a wife named Vomi, who also worked as a scientist in the Red Ribbon Army, and a son named Gevo. A tall, muscular, and redheaded young man. He was a soldier in the Red Ribbon Army.

Based on Dr. Gero’s wife, Vomi, who died years before the beginning of the game’s story, she was presented as a benevolent scientist looking to continue the research of her creator.