The residents of Sesame Street did not invite Mr. Snuffleupagus with them to find Big Bird in the film "Follow That Bird" because at that point, they still didn't believe he existed.
He would be revealed to the cast a few months later.
Discussion
Yes, but do you know the reason why they changed the Snuffleupagus character?
"In this day of child abuse, we felt it important for children to feel they could talk to adults and be believed," the show's executive producer, Dulcy Singer, said at the time. "We didn't want to do anything to discourage children from going to their parents."
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