By my count, this is the third episode, not counting the Pilot, to deal with Sam and Dean’s “daddy issues.” In the Pilot, we saw happy-daddy John transform into a hunter. In Bugs, we heard Sam talk about how dissatisfied he was with his childhood and how he wasn’t sure if John wanted to see him at all. In Home we saw a still-grieving man staying away from his boys even though he wanted to see them. In Scarecrow, three episodes before Nightmare, we saw John call the boys on the phone and speak kindly to Sam before cracking down into drill sergeant mode.
John doesn’t show up at all in Nightmare, but he’s lurking between the lines throughout the episode. He’s clearly on Sam’s mind, perhaps almost from the beginning.
When Sam and Dean talk to the Millers’ neighbor to get details about Jim Miller’s death, she tells them, “Oh, his poor family. I can’t even imagine what they’re going through.” Sam looks away and seems very upset. He may have been upset only because he felt guilty for not getting there soon enough to prevent Jim Miller’s death, but I think there may have been more to it.
For the past several months, Sam has been trying to track down his father, whom he hasn’t seen in years and with whom he argued the last time they were together. He knows that John is in danger, pursuing the demon that killed Mary. When he spoke to John on the phone in Scarecrow, the first thing he asked was, “Are you hurt?” So, in this situation--a middle aged man, a father who drives an old/classic car and listens to classic rock, a man Sam feels some strange connection with is killed--perhaps he’s thinking that he *can* imagine what the family’s going through.
Later that day, Sam talks to Max, and Max says that Jim Miller was “a normal dad,” and indicates that he’s living there while he saves money for college. Again, John Winchester pops up between the lines. Normal is a watchword for Sam, and he’s made it clear in the past that he doesn’t consider the way John raised him and Dean to be normal. And, of course, John didn’t support Sam’s college plans. At this point in the episode, Sam may be envying Max his father and his childhood.
Later, when Sam and Max talk again after Roger Miller’s death, Max again states, “We were totally normal. Happy.” However, when Dean and Sam dig into the family’s background, they find out that Jim and Roger Miller both physically abused Max and that Jim Miller was “a mean drunk.”
Because of what Sam says later in the episode, that he “can’t begin to understand what [Max] went through,” I wonder if at this point Sam feels some twinge of guilt for the (apparent) lies he told to Jess in the Pilot, when he implied twice that John was pretty much a worthless drunk. We don’t know for a fact from the conversations in this episode that John didn’t ever have (or flirt with) some kind of drinking problem. However, when Sam says that he can’t begin to understand Max’s experience, it makes me think that what he said in the Pilot was at the very least a major exaggeration.
When the whole truth comes out in the conversation between Sam and Max, when Sam and Dean have gone to the Miller’s house to confront Max, I think we see a distinct illustration of what John gave to his sons versus what Jim Miller took from Max. Except for his new telekinetic abilities, Max made it clear that he always felt helpless and powerless. “My whole life I was helpless,” he says. His decision to kill his father and uncle “was about not being afraid.”
We can easily compare Max to Sam and Dean, who were raised to be strong, to be able to protect themselves and others, to be afraid only when necessary for self-preservation. Sam may complain about being raised like warriors, and there are certainly many arguments against John’s child-rearing methods, but nonetheless he gave his sons a great deal of strength and confidence. Jim Miller took those things away from Max.
Again, despite his odd methods, John Winchester gave his sons his love. Max says to Sam, “When my dad used to look at me, there was hate in his eyes. Do you know what that feels like?” Sam answers simply, “No.” Sam and John apparently argued quite a bit, at least when Sam was in his late teens, but Sam still clearly knew he was loved. John may have looked at him with anger or frustration or even disappointment, but not hate.
Max also says that his father blamed him for his mother’s death, a death that parallels Mary’s death in Sam’s nursery. Sam doesn’t seem to identify at all with being blamed that way, so apparently John never laid that burden on Sam. The final mention of fathers in Sam and Max’s discussion is when Sam reveals that his father saw Mary die the same way Jim Miller saw Max’s mother die. Max says, “Then your dad must have been as drunk as mine.” Again, Sam answers simply, “No.”
Later, as Sam and Dean leave the Miller house, Sam reveals to Dean that he’s pretty much done a 180 in his opinion about their father, as opposed to what it was earlier in the season. “Well, I’ll tell you one thing—we’re lucky we had Dad…Well, he could’ve gone a whole ‘nother way after Mom. A little more tequila, a little less demon-hunting, and we would’ve had Max’s childhood. All things considered, we turned out okay—thanks to him.”
At this point, I think Sam is starting to see that the demon-hunting was actually a functional response to seeing your wife killed by supernatural forces. This experience of seeing all-too-human horror behind the mask of the “normal” family he always yearned for probably gave him some appreciation for the fact that his childhood could have been much worse than it was. Through his reactions to Max, Sam has told us a lot about what John *wasn't* as a father: he wasn’t a violent drunk; he didn’t physically abuse them; he didn’t show contempt for them; he didn’t blame Sam for Mary’s death.
That leaves a lot of latitude for how exactly John was as a father, but given how he’s sometimes perceived in fandom, it’s valuable information.