It's Punky Brewster S01 E18 Double Your Punky

Will the real Punky Brewster please stand up?: While Punky is at a school picnic, Glomer creates a clone of her from a photo to keep him company at home. But he creates an obnoxious Punky who escapes. In his confusion, Glomer zaps the sweet Punky back into the photo and throws it away.