Shelby Corcoran is a recurring fictional character from the Fox musical comedy-drama series Glee. Portrayed by actress Idina Menzel, Shelby was introduced in the fourteenth episode of the show as the coach of Vocal Adrenaline, a rival show choir to New Directions, the show's primary musical group. Fans had lobbied for Menzel to be cast as Rachel Berry's biological mother, due to the strong physical resemblance between Menzel and Michele. After it is revealed that Shelby is, in fact, Rachel's biological mother, Shelby discloses that she had signed a contract that stated that she could not seek out her daughter until she was eighteen. She tells Rachel that instead of trying to act like mother and daughter, they should just be grateful that they have met, and maintain a distance.

"Dream On" is the nineteenth episode of the American television series Glee. The episode premiered on the Fox network on May 18, 2010. It was directed by Joss Whedon and written by series creator Brad Falchuk. Neil Patrick Harris guest-stars as former glee club star Bryan Ryan. Working as a school board auditor, he threatens to cut the glee club out of the budget, bitter at never having attained his own show-business dreams. Rachel attempts to find her birth mother, and Artie struggles with his desire to walk. The episode title is a reference to Aerosmith's song "Dream On", also performed during the episode.