Prue Halliwell : Prue was the oldest sister of the Charmed Ones . Prue 's death is not established until the premiere episode of the fourth season , `` Charmed Again '' , in which we begin the season with an anguished Piper trying to resurrect her spirit . Instead , the sisters ' grandmother appears , telling her that Prue is safe and with their mother and that seeing her now would only hurt her chances at accepting that Prue was not going to come back .