The cousin of the late Gwen Stacy, Jill moved to New York City with her father and brother, Arthur and Paul. She befriended Peter (
Spider-Man) and Mary Jane Parker, taking classes with Mary Jane at Empire State University (ESU). Jill sought to understand the events surrounding Gwen's death, and though hesitant, Peter eventually told Jill his side of the story.
Jill was nearly killed when caught in a crossfire during an attack by one of Norman Osborn's men on the Parker's home. When it appeared that Peter was widowed by a deranged individual known only as the Stalker (who had kidnapped Mary Jane), Jill made romantic advances upon him. She withdrew when Mary Jane was found to be alive.