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Yeaster Doozer is, along with Crusty Doozer, one of the two elderly Doozers remaining from the original Doozer colony at the Cavern of Lost Dreams.

She was introduced in the third season Fraggle Rock episode "The Cavern of Lost Dreams. She and Crusty are reintegrated into the current Doozer community. Yeaster re-appears in "Gunge the Great and Glorious," to assist in keeping Gunge entertained by bringing in a Fraggle postcard.