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Dean: “Screw the job.”
Sam: “You can’t run from this.”
While Sam and Dean also often argue over their views of their dad and how to deal with particular hunts, they are undoubtedly devoted to each other. Each would willingly die for the other. Dean is Mr. Keep Everyone at Arm’s Length, but his family is everything to him. After his father’s death, Sam is his only family. He’s been watching after Sammy his entire life, and he’s not going to stop now. We see the depth of that devotion over and over, as in “Born Under a Bad Sign” (2-14) when Sam asks Dean to kill him. Dean says, “I can’t. I’d rather die.” Sam was possessed by a demon at the time, but Dean didn’t know that. Even thinking Sam was starting to give in to evil, he couldn’t kill his little brother.
This not being able to let go of Sam is pushed to the extreme when Sam dies at the hand of Jake in “All Hell Breaks Loose, Parts 1 and 2” (2-21 and 2-22). In ironic contrast to what he condemns Evan for in “Crossroads Blues” (1-8), and the action for which he’s angry at his dad, Dean makes a deal with the Crossroads Demon to bring Sammy back to life in exchange for his own soul. Even when the demon only gives Dean one year to live versus the customary ten, Dean makes the deal. And he makes no apology for it when Bobby figures out what he’s done and confronts him about it.
Dean: “I couldn’t let him die, Bobby. I couldn’t. He’s my brother.”
Bobby: “How’s your brother going to feel when he knows you’re going to hell? How’d you feel when you knew your dad went for you?”
Sam shows that same unwillingness to let go of Dean in “In My Time of Dying” (2-1). When he and Bobby are looking at the demolished Impala, this exchange shows that Sam is not about to give up on Dean.
Sam: “Oh man, Dean is gonna be pissed.”
Bobby: “Look, Sam...This just ain’t worth a tow. I say we empty the trunk and sell the rest for scrap.”
Sam: “No. Dean’d kill me if I did that. When he gets better he’s gonna want to fix this.”
Bobby: “There’s nothing to fix. The frame’s a pretzel, the engine’s ruined. There’s barely any parts worth salvaging.”
Sam: “Listen to me, Bobby. If there’s just one working part, that’s enough. We’re not just gonna give up on...” (voice trails off)
Bobby: “Okay. You got it.”
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The type of dedication Sam and Dean show each other is powerful, the Supernatural world's equivalent to what many of us would do for a loved one -- anything possible to save them from certain harm or death.
So, what's your favorite Supernatural moment that shows this intense family dedication?