The Jack turned round to say something like "if you think I'm drunk, the go upstairs and see who's the drunkest - my father or I". Which indicated that his farther is there in the hospital. Another thing that indicated his father was still alive, was that the drug prescription was signed by his father.
Well season four has started and its just as good as ever and none of your questions have been answered lol, I dont think even the writers know whats going on lol