Dean was sleeping, peacefully, for once. With alcohol in his bloodstream his body, his mind, were relaxed and he didn't have to get up until - "Dean!" He opened his eyes reluctantly, half-up on instinct. "Dean!!" Sam shouted again, way too loudly for his liking. Dean blinked blurrily and rubbed at his eyes to clear the image infront of him. It was his brother, soaking wet and carrying an equally drenched boy in his arms. "What?! Who is-." "This is Adam Milligan. He was staking us out in a car outside. He says he's looking for his father: John Winchester." It took several seconds for Dean to process this but he was on his feet in a matter of moments. "He's lying! It's a trick, a demon - have you checked to see if-."
"I've checked Dean! And he was carrying this!" He roughly deposited the boy on his bed and lobbed something at his brother, who almost dropped it, his skills softened by cheap shots. He peered at it critically. It was an old photo, it seemed, faded and worn but clear in the identity of the smiling person depicted.
"Dad." He couldn't help but voice it out loud. The pain of losing him would always be raw. John was grinning freely, looking away from the camera, wind-blown and healthy, he couldn't be more than 25. He flipped it over. There was some elegant hand-writing on the back, faint but readable to someone as trained as Dean:

'John (Winchester) August 15th 1988. Brookeview Hill.'

Dean had to read it a few times in his shock, but his brain quickly did the math. "Dad was on a hunting trip...in...Montana then. He couldn't have...Mom!" He met Sam's gaze, stricken. They just looked at eachother for a long moment, then the younger man spoke: "You know he could have. Mom died in '83 and those hunting trips he used to go on weeks at a time. Stands to reason he'd be lonely." Sam sat heavily on his bed, both of them forgetting the boy. "But what about Mom?! And...and Dad - Dad would never have...but he would have told us!" Sam shrugged. "Guess he never knew."
"Oh God..." Dean rubbed his face, feeling a headache coming on,"That's him?" He looked over at the boy's still form.
"That's him." The older man stood unsteadily and walked over to the bed, to this...child. He stared down without saying anything for a while and Sam turned where he was sat to do the same. The boy was soaked and pale-looking. But there was a tan visible on his face and neck as though he'd been travelling for a long time. He looked vulnerable in his lack on consciousness ("what did you do to him?" "I didn't! It was raining so hard, I couldn't see him! I knocked him out before I had time to think!" "Sam!") He must have been not much older than 18, at most. He was wearing a khaki jacket and t-shirt with combats and hard-wearing boots. Round his neck was a pentacle on a chain...protection against evil. They both looked at eachother. "Could just be a coincidence." Sam reasoned, but they both knew it was a pretty massive coincidence when it involved them: i.e. NOT a coincidence. "We need to get him out of those clothes - he'll catch pneumonia or something..." "I'll do it," Dean stretched and headed for the chest of drawers, "Go have a shower." "Fine. If he wakes up, be nice."
"I'm always nice!" The shorter man flashed a brillant smile and Sam rolled hsi eyes as he went into the bathroom. There was a silence in the small motel room, punctuated by the lashing summer rain outside. The light-haired man busied himself choosing from his limited clothes-range, holding up items and discarding the unsuitable. Eventually he found a pair of sweats and a t-shirt and settled them on Sam's bed as he methodically undressed then re-dressed the boy. He looked even smaller in his slightly too-big clothes, even younger, if that was at all possible. Something about his face, the curve of his jaw reminded him of Dad, a stubborness around his mouth...but he was probably just seeing things that weren't there, ironically...He made a quick decision and pulled the covers as effectively as possible around Adam to keep him warm, towel-dried his hair off with a shirt to stop the worst of the chill and felt his forehead to check he wasn't burning up. Nope. Everything seemed good. The child was breathing peacefully and regularly, deep breaths, clearly asleep after Sam's over-excitied efforts at self-defence. As he fluffed up the pillows, double-checked the duvet and made sure the heating was on Dean had a pang of nostalgia, remembering when Sammy was just a kid, when he was just a kid and would take care of his younger brother like this. This sort of thing came so easily to him, it felt instinctive, natural, almost on par with a good hunt. And now he had another...brother, another younger brother to look after. What were the chances?! He felt so sad, so emotional for a moment as he thought how John had never known about this kid, had never known he had a third son, healthy and normal like this. He was in their care now, they would take care of Adam in their Dad's place. It was their duty as brothers to proect their family. Family was always the most important thing, even the knew members. "Is he alright?" Sam interrupted guiltily as he approached, roughly rubbing his hair with a towel, another round his waist. "Yeah, he's fine." The dark-haired man sat on Dean's bed and finished 'drying' his hair, throwing the towel aside as he rumaged in the drawers. He found a t-shirt and pulled it on, watching his two brothers in reserved awe at the situation.

*jumps to later on but I will edit and add the missing part*

They were all getting into a happy stage of drinking when a fourth man suddenly appeared (out of thin air, it seemed) in their midst. Adam noticed him first.
"What the-?!" "Dean." Intoned the man ominously. He was relatively tall- not Sam Winchester tall - but tall enough to intimidating, the blonde thought. He had dark brown, almost black, hair and ridiculously blue eyes. He was wearing a tan trench coat, shirt, tie and black trousers as though he was some kind of accountant or something. He looked tightly wound up like he might explode any second. "Oh for Fuck's sake!" Dean almost yelled, throwing his can to the side and getting unsteadily to his feet, "Can't you see we're BUSY?!" Adam wasn't sure which part he was most disturbed by - the fact that Dean knew the magic-man, or that he was now shouting at him, when the guy obviously wasn't in 'the mood'. There was an aura of power surrounding the accountant and Adam knew he wouldn't be shouting at him if he could at all help it. Sam stayed quiet as the two men faced off. Drunk as he was, Dean looked absolutely livid, fists clenced at his sides, tension evident in every angle of his body. The visitor looked angry and very dangerous.
"Dean," began the blue-eyed man again, "God has need of you."
"Well he can just go-." "Dean!" Interrupted Sam before his brother could go any further with his choice phrase. The smaller Winchester, surprisingly, held his tongue and seethered quietly to himself for several seconds, then:
"If you're so high-and-mighty you must know who THIS is." He motioned towards Adam, who jumped at the inclusion and blanched, tightening his grip on the bed. "Your brother." Answered the accountant simply. "Yeah. Our LOST brother. Can't we have one day with him before the planet goes to shit?" The visitor stared at Dean for a long moment, his anger quickly disappating and a mixture of weariness and empathy dawned in his stunning eyes. "I'm sorry," he muttered, in what Adam considered a shocking submission, "My orders..."
"Are a load of rubbish. Sometimes." He added swiftly. "They are confusing..." The accountant finished softly, sitting on the blonde's bed and rubbing his eyes absently with slender hands. "Cas," the man looked up, whole pose screaming 'vulnerable', "Cas, won't you stay and relax for a bit. Get to know...us." It seemed like the visitor - Cas - was going to disagree, when Dean crossed the room with a bottle of beer and physically pressed it into the man's hand. "Come on, you don't know what it's like to be human 'till you've been a bit smashed!"
"Smashed?" Queeried Cas curiously, holding the drink up to his eyes and peering into its amber depths.
"Wasted. Drunk. Hammered."
"Isn't this toxic to humans?" They all laughed.
"Yeah. That's the point. Come on Castiel, live a little. Might not work on you anyway, wonder what'll happen...?" There was a moment of suspense as the dark-haired man considered the beer, then took a careful mouthful, swallowed.
"Tastes...different." He mused, taking another swig,
"Wonder if your vessel gets drunk..." Dean was scrutinising 'Castiel', now, a fresh can of lager in his own hand. "He is pious. I'm not very certain on this," He glanced back at his half-empty botte,"Area." "So, what's going on?" The youngest brother finally picked up the courage to interrupt this...bizarre conversation. He was already quite tipsy, so it probably wasn't hitting him with quite as much force if he had been stone-cold sober. They all looked towards him, as though just realising his existance. "Oh, uh, Adam, this is, uh...Castiel." Dean offered lamely, looking unsure what his next move was. Castiel got to his feet, beer in hand. Adam copy-catted the action and they stood aukwardly for a couple of seconds. "Adam." The blonde stuck his hand out. The dark-haired man's eyes rested on his hand, then he reached out and took it firmly. "I am Castiel. A warrior of God."
"A warrior of?"
"An...angel."
"Angel?!"
"Yes."