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2019 Kennedy Center Honoree co-founder of “Sesame Street,” Lloyd Morrisett, arrives at the State Department for the Kennedy Center Honors State Department Dinner, in Washington 2019 Kennedy Center Honors, Washington, USA - 07 Dec 2019

Sesame Streetco-creator Lloyd N. Morrisett has died,according to a tweetfrom Sesame Workshop. He was 93.

“Sesame Workshop mourns the passing of our esteemed and beloved co-founder Lloyd N. Morrisett, PhD, who died at the age of 93,” read the post on Tuesday from the nonprofit organization behindSesame Street.

A cause of death has yet to be revealed.

“A Lifetime Honorary Trustee, Lloyd leaves an outsized and indelible legacy among generations of children the world over, with Sesame Street only the most visible tribute to a lifetime of good work and lasting impact,” another tweetaddedof Morrisett.

AlongsideJoan Ganz Cooney, Morrisett created the renowned children’s series in 1969 in the middle of the Civil Rights movement.

The organization described the show as a"simple but revolutionary idea"to help disadvantaged children prepare for school through animation, puppetry, and live-action sketch comedy.

Included withSesame’s Streetannouncement on Tuesday came a statement from Cooney, in which she mourned the death of her fellow co-creator and emphasized his impact in children’s television.

“Without Lloyd Morrisett, there would be no Sesame Street,“she said. " It was he who first came up with the notion of using television to teach preschoolers basic skills, such as letters and numbers.”

“He was a trusted partner and loyal friend to me for over fifty years, and he will be sorely missed,“she added.

ZACH HYMAN/Patrick McMullan via Getty

Rosita, Abby Cadabby, Joan Ganz Cooney, Elmo, Lloyd Morrisett, Zoe and Grover attend SESAME WORKSHOP’S 7th Annual Benefit Gala at Cipriani 42nd Street on May 27, 2009 in New York

In 1970, he helped found Sesame Workshop, which prides itself as “a community built on diversity, equity, and inclusion, where creators, educators, partners, and beloved characters come together to help kids grow smarter, stronger, and kinder,“according to their website.

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Morrisett’sbiography on the websitealso states that he became a Lifetime Honorary Trustee after serving 30 years as Chairman of the Workshop’s Board of Trustees for the organization.

source: people.com