According to McGrath, the show will keep Loretta Long, who has played Susan, Gordon's wife, since the beginning of the show.

McGrath, 84, had been with the Sesame Street cast since the show's inception in 1969 -- one of only two of the original cast members still with the show until this year. Formerly a successful singer in Japan, McGrath sang on many of the show's early hit songs, such as "People in Your Neighborhood":

https://www.youtube.com/watch?v=V2bbnlZwlGQ

Delgado, 76, joined the show in 1971, debuting as Luis the handyman at the same time as Raul Julia's character Rafael. (Julia would go on to be a movie star before dying in 1994.) Later, Luis married Maria, played by Sonia Manzano, and the two would be instrumental in introducing Hispanic culture to Sesame Street viewers. (Manzano retired from the show in 2015.)

Though he wasn't the original Gordon, Orman had played the character since 1974. Gordon was the patriarch of the Robinsons, an African-American family that had been on Sesame Street since the beginning. Orman also played "Trash Gordon," a superhero made up for stories told to Oscar the Grouch.

In his memoir Sesame Street Dad: Evolution of an Actor, Orman wrote:

"If I could boast of no other major career accomplishment, having played a central role as I have in the development and continuation of this landmark series would alone have made my life sufficiently meaningful. The historical significance of Sesame Street and its surprising longevity have made my association with the show, in many regards, my life's crowning achievement."

McGrath said the cast changes were made as part of a major overhaul the show has undergone since its producers made a deal with HBO last year. In addition to cutting the show from an hour to a half-hour, McGrath remarked, HBO will premiere the newest episodes on HBO for nine months before they're made available elsewhere, and change the focus to topics such as "self-regulation" and "executive function."

UPDATE: Elizabeth Fishman, a representative from Sesame Workshop, reached out to KQED and provided this statement:

Bob McGrath, Emilio Delgado (“Luis") and Roscoe Orman (“Gordon") remain a beloved part of the Sesame family and continue to represent us at public events. To us, and for millions of people worldwide, they are a treasured part of Sesame Street. Since the show began, we are constantly evolving our content and curriculum, and hence, our characters, to meet the educational needs of children. As a result of this, our cast has changed over the years, though you can still expect to see many of them in upcoming productions. As we’ve stated previously, Sesame Workshop retains sole creative control over the show. HBO does not oversee the production.

UPDATE: Sesam Workshop reached out to McGrath, Orman and Delgado to see about bringing back to the cast. Read more here: ‘Sesame Street’ Looking to Bring Back Senior Cast Members After Uproar

Read more: Five Times Bob, Luis and Gordon from 'Sesame Street' Taught Us to Be Better

