On 'Good Morning America' (weekdays, 7AM ET on ABC), six cast members from 'Welcome Back, Kotter' reunited and fondly recalled the seminal sitcom. In particular, John Travolta thanked Gabe Kaplan for giving him a start in acting, and Kaplan revealed the origin of Vinnie Barbarino's catchphrase.

"I've waited thirty-five years to thank this man," Travolta said, gesturing to Kaplan. "I never got to publicly thank Gabe for his genius, his putting us on the map. You know, we all wouldn't be here today without Gabe."

Kaplan explained that Barbarino's catchphrase was derived from an actual saying among kids. "It was based on what they really said in Brooklyn in the 50s," he said, adding that the original phrase was somewhat vulgar and needed to be cleaned up for television. "We couldn't do that so we came up with 'Up your nose with a rubber hose.'"

Cast members Marcia Strassman, Lawrence Hilton-Jacobs, Robert Hegyes and Ellen Travolta also appeared on the panel.