Gone

Fanfic by The Angst Guy, an alternate-history story in which the Cuban Missile Crisis of October 1962 leads to atomic war. The story focuses on Helen Barksdale, a teenager who must not only survive the chaos but rescue her two sisters as well.

Trivia
The birth order used in the story, with Helen being the oldest of the three Barksdale sisters and Rita and Amy being (in order) the next oldest, was contradicted by information in a recent interview with Glenn Eichler, who stated that Rita was the oldest and Helen was the middle child. However, nothing presented in the Daria TV series indicated that this was the case, so this background element never made it into production, and the story can stand as is without contradicting canon.