Eddie Haskell was a great character. During a time in which bad boys like him were usually portrayed as unkempt and disrespectful, Eddie was always well groomed and respectful. He would enter the Cleaver house looking like he was going someplace formal, compliment Mr. and Mrs. (especially Mrs.) Cleaver and then go off and get into trouble with Wally. I could never decide whether he was essentially a "good" or "bad" kid. I suppose that that's the genius of the character and how well Osmond portrayed him. For anyone who hasn't bothered to read the linked article, it was mentioned that Eddie was supposed to be just a guest role, but Ken "knocked it outta the park" and was turned into a series regular.