Elizabeth resided in an Institute with her family. During the early days of the Dark War, Elizabeth's mother had apparently been one of the first Shadowhunters to be forcibly Turned into Endarkened soldiers by Sebastian Morgenstern. Afterwards, she, their Institute received the order to evacuate to Alicante, she did so immediately with her sister, Julie, and presumably their father.
During the last night of the Dark War, Elizabeth and Julie were among the children locked up in the Accords Hall for safety. However, the faeries of the Wild Hunt unexpectedly made it inside the building. She was one of the many casualties, and Julie witnessed the very moment the faerie, whom Julie noted was beautiful and had silver hair, struck her down with his sword.