Guest Stars Jesse Williams as Dr. Jackson Avery Sarah Drew as Dr. April Kepner Jason George as Dr. Ben Warren Nora Zehetner as Dr. Reed Adamson Alan Mandell as Henry Stamm Emily Bergl as Trisha Marion Ross as Betty Donahue Austin Highsmith Garces as Amber Courier Amy Farrington as Mary May Demi Lovato as Hayley May Jonathan Goldstein as Ken May Co Starring Mark Saul as Dr. Steve Mostow Gloria Garayua as Dr. Graciella Guzman Regi Davis as Dr. Kevin Fisher Denice J. Sealy as Nurse