Model Misbehavior is episode 10 of family guy season 04. It was originally aired on July 24, 2005.
When the Griffins visit Lois’ parents, Lois realizes that her father prevented her from fulfilling her lifelong dream of becoming a model, so she returns to Quahog and hits the catwalk. Lois is an instant hit, but the glamorous world goes to her head and Peter has to step in to get her back on track. Meanwhile, Stewie starts a pyramid scheme business and hires Brian as his assistant.