Caroll Spinney, the man who worked behind the scenes as the puppeteer on Sesame Street for 50 years, has died at the age of 85. He played such beloved characters as Big Bird and Oscar the Grouch.

According to a statement released by the Sesame Workshop, Spinney passed away Sunday, December 8th, at his home in Connecticut due to complications from Dystonia.

“Caroll was an artistic genius whose kind and loving view of the world helped shape and define Sesame Street from its earliest days in 1969 through five decades, and his legacy here at Sesame Workshop and in the cultural firmament will be unending,” the statement reads. “His enormous talent and outsized heart were perfectly suited to playing the larger-than-life yellow bird who brought joy to generations of children and countless fans of all ages around the world, and his lovably cantankerous grouch gave us all permission to be cranky once in a while.”

According to a New York Times profile on Spinney published last year, the Waltham, Massachusetts native appeared in over 4,400 episodes of Sesame Street. He retired as a puppeteer in 2015, but continued to voice Big Bird and Oscar the Grouch for episodes airing as recently as this year.

After crossing paths at a puppeteers festival, Spinney was hired by Sesame Street creator Jim Henson in 1969. He quickly made his presence felt, especially when it came to the character of Big Bird. “I said, I think I should play him like he’s a child, a surrogate,” Spinney told the Times. “He can be all the things that children are. He can learn with the kids.”

Over the course of the next five decades, Caroll’s “unparalleled career saw Big Bird visit China with Bob Hope, dance with the Rockettes, be celebrated with a star on the Hollywood Walk of Fame and a U.S. postage stamp, and named a ‘Living Legend’ by the Library of Congress,” Sesame Workshop noted in its statement.