Gerta

Gerta the Goatmilker is an apparent jokester from Norway. (or maybe even Wherever it is Rolf comes from). and apparently Edd's penpal. Gerta sent Ed (who is another penpal) many Wolf-related items, which made Rolf think that Ed was an accomplice of Wolf (Rolf's worst enemy), and had been sent these items (a wolf-chasing-a-sheep old world music box, and a wolf pelt, to be more precise) as a sign that he was back (or at least still at large). but then at the end of the episode, Edd was sent a so-called "Feather-duster of Tomfoolery", which confirmed to Rolf that it was GERTA that truly sent the items, not Wolf.