What is the name of Victor's adopted sister and later wife?

Victor Frankenstein's adopted sister and later wife is Elizabeth Lavenza. She is one of the central figures in Mary Shelley's Frankenstein; or, The Modern Prometheus and represents Victor's loving connection to family and ordinary human life.

Elizabeth's background differs between the novel's two major editions. In the 1818 version, she is Victor's cousin from an Italian family and is adopted by the Frankensteins after her mother's death. In the revised 1831 edition, she is an Italian orphan whom Victor's parents find and adopt. Victor still calls her his “more than sister,” but the later version removes their blood relationship.

Elizabeth and Victor eventually marry, but their happiness is short-lived. After Victor destroys the unfinished female companion he had promised to create for the Creature, the Creature vows to be with Victor on his wedding night. The threat is fulfilled when Elizabeth is murdered in the bridal room. A common mix-up comes from film adaptations, where Elizabeth's relationship to Victor and even her name can change.