You hear a lot of echoes throughout Ashlee Simpson's Autobiography, but her big-eyed, bright-smiled sister Jessica isn't behind a one of them. That'll come as no surprise to fans and anyone who has caught the "darker" Simpson sister on MTV, which is responsible for hurtling the hard-edged "Pieces of Me" onto radio playlists across the country and creating a mini frenzy over this CD's content. Stoking the gossip-fueled flames is track three, "Shadow." On it, 19-year-old Ashlee spills her childhood resentment over her sister's attention-gulping career, ending up on a conciliatory note that has the surprising effect of making the Simpson divas' drama seem believable ("Everything's cool now…and the past is in the past," she sings). But serious music fans ought not to dilly-dally with the celeb stuff and dive right in, because this disc dishes up more than a lot of us bargained for. "LaLa" revs up the unsuspecting by way of out-and-out lustiness, "Love for Me" lays on the lovelorn angst thick, and the title track is a take-no-prisoners, love-me-or-leave-me rock anthem. Rippling throughout are cunningly malleable vocals, bending here for a kittenish Gwen Stefani effect, stretching there to sound Christina Aguilera-cathartic. Sweeter moments call to mind the indie sensibilities of Jill Sobule. More than others of her reality-show insta-star ilk, Ashlee Simpson's is an autobiography that shouts, "bring on the sequel."