T9, E7: Abby fears the worst when her brother, Eric (recurring guest star Tom Everett Scott), suddenly disappears. Carter and Chen treat a frightened Chinese immigrant nanny, Tong-Yi (Michelle Krusiec), whom they suspect was impregnated by her employer. Meanwhile, new surgical resident Paul Nathan (recurring guest star Don Cheadle), who is struggling to overcome a physical disability, tries to help in the emergency room--but his fellow doctors do not appreciate his advice to patients. Unable to quench his sexual appetites, Kovac also gets into trouble in his professional life, despite his admirable resolve to find an eye specialist to treat a young gunshot victim. Gallant and fellow medical student Erin Harkins (recurring guest star Leslie Bibb - "Popular") engage in an escalating competition of medical knowledge. And Weaver gets some much-needed good news.