Ashlee Simpson should just shut ... her ... mouth. Simpson, the little sister - image-wise, the evil princess - of Jessica Simpson, the good fairy, has found herself bobbing in boiling water for months. Some of her woes are warranted. Most are starting to take on a gladiatorial feel. Victim, meet lion. Lion, gnaw at will. First came Ashlee Simpson's appearance on a venerable Saturday Night Live episode. A miscued guide-vocal track - something used often and by far more respected singers than Simpson - created a debacle every bit the equal of Janet Jackson's infamous "wardrobe malfunction" at last...