'Supernatural' convention scares up Jeffrey Dean Morgan for return to Pittsburgh

The "Supernatural" convention is coming back to Pittsburgh, and this time Sam and Dean's dad is tagging along. Jeffrey Dean Morgan -- the cheerfully sadistic Negan on "The Walking Dead" and the heartbreaking Denny Duquette on "Grey's Anatomy" -- also plays John Winchester, father to "Supernatural's" Sam and Dean -- Jared Padalecki and Jensen Ackles.