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Doc, inadvertently revealing his affection for Ms. Ardath over the phone, much to Sprocket's amusement

Ms. Ardath (first name Betty) moves next door to Doc's workshop, opening up the Captain's Inn bed-and-breakfast, on Fraggle Rock. First mentioned in the second season episode "A Cave of One's Own," Doc was initially resistant to her presence, but is won over by her charm and soon works part-time at the Inn, performing many odd jobs. Occasionally, Sprocket teasingly implies that Doc has a crush on Ms. Ardath, and Doc's own behavior does not contradict such a conclusion. Ms. Ardath owns an airedale named Marigold, who Sprocket himself is in love with.

Ms. Ardath is implied to be attractive and comparatively young in contrast to Doc (in "The Perfect Blue Rollie," she celebrates her 39th birthday), but like the inn itself, or fellow neighbor Ned Shimmelfinny, Ms. Ardath is never seen onscreen.