Jane Henson, the puppeteer who helped make The Muppets a household name alongside husband Jim Henson, has died, the Jim Henson Co. announced late Tuesday. Age 78, Jane passed away on Tuesday, April 2 following a "long battle with cancer," the company explained.

Jane met Jim Henson in a University of Maryland puppetry class in the mid-1950s. Together, the twosome forged a creative and business partnership and developed the Muppets -- the beloved universe of puppets that includes Kermit the Frog, Miss Piggy, Elmo and many other characters that appeared on Sesame Street, The Muppet Show and a slew of hit films.

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The couple married in 1959 and had five children: LIsa, Cheryl, Brian, John and Heather. Jim and Jane separated in 1986, and Jim Henson died in 1990. She established the Jim Henson Legacy in 1992, the National Puppetry Conference at the Eugene O'Neill Theater Center and the Jane Henson Foundation for philanthropic work.

"Jim wanted to leave the world a better place," she often said during speaking engagements. Adds Arthur Novell, Trustee of the Jim Henson Legacy: "most would agree they both did." A memorial Mass is planned for next week.

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Donations in Jane's memory can be sent to the Center for Puppetry Arts, the Jim Henson Foundation for the support of puppetry and the Puppetry Conference at the Eugene O'Neill Memorial Theater Center -- information at Henson.com

This article originally appeared on Usmagazine.com: Jane Henson Dead: Muppets Co-Creator Was 78