Shamelessly stealing this plot bunny from libertybelle's tumblr: "Someone so sick that they don’t even stick their head out from under the covers. They are a shapeless heap of quiet, sniffling unhappiness. Mmmaybe the ends of messy hair sticking out from one end. Maybe. If that. The only indication they’re awake is the occasional, lengthy shivering of breath, followed by a cataclysmic earthquake shudder of blankets as they sneeze." This bunny was born to be a Sam fic , IMHO. :)

Shapeless Heap of Quiet, Sniffling Unhappiness

Dean could barely keep his mind on the drive. He had the windows down, letting the cool night air blow into his face. He had the tape deck turned up, letting the repetitive metal guitar rift fill his ears. And he had his cell phone out, resting on his thigh, just in case it rang.

It didn’t. Damn phone. Dean picked it up and glanced down to make sure it was still on. It was. But it wouldn’t ring. “Fuck this.” He tossed it onto the empty passenger seat and pushed down on the accelerator. The speedometer went up another seven, nine, twelve miles an hour. When he made it back in record time, it wouldn’t even matter that the phone never rang.

Dean’s foot didn’t leave the pedal until the floodlight illuminating the Singer Self Service Salvage Yard came into view. And he didn’t stop glancing at the phone, even as he walked up to Bobby’s house. “How is he?” was the first thing he said, even before saying hi to Bobby or telling the older hunter how the hunt had gone. It had gone well, incidentally, but it probably would have been easier with backup.

Cas was out of the picture right now. Bobby was stuck in a wheelchair. And Sammy was just getting through another bout of demon blood detox. Which meant that the haunted island cabin had been Dean’s and Dean’s alone to handle. So he had. That’s what Dean Winchester did.

“He’s, uh… look, son, I meant to call ya back, but—“ His eyes darted not in the direction of the demon-proof safe room but the bedrooms.

Dean was down the hall at once, not even breaking stride. He got to the guest bedroom, packed full of bookshelves hidden behind everything from a gun rack to taller stacks of books. Up against one wall, though, was a small twin bed. And in the center of that bed was a lump Dean took to be his brother.

Sammy had burrowed completely under the covers and had curled up into the smallest ball his gigantor body would allow. It almost seemed impossible for this lump to be his brother. It didn’t really move. It didn’t really resemble anything apart from a pile of laundry covered in covers. It didn’t really say anything. All it did was sit there and sniffle quiet little miserable sniffles.

And that was when the worry really hit Dean. What had Bobby been trying to warn him about? What was wrong with him? Before Dean had left for the hunt, he’d made sure that Sammy had been through the worst of the detox—the hallucinations and the withdrawal symptoms. But had he slipped back into it all somehow already? Or was it something worse?

Had a demon come after him, gotten to him? Had he tasted its blood? Had it forced its way inside? Was this actually his brother here and now? Or was it some black eyed fucker luring him in close to pull a Red Riding Hood Wolf trick on him? Was it about to leap out from under the blankets and come at him? Acting on instinct and driven by fear, Dean had already reached for his knife. “Sammy? Sammy, are you all right under there?”

There was no answer, apart from a soft grunt and another sniffle. Something was definitely wrong. Sam had been weak before Dean left, sure. Demon blood detox nearly killed him. If something had taken advantage of him in that weakened state… something Bobby hadn’t been able to prevent… something Cas hadn’t been able to drive out… “Sammy? Talk to me.”

There was a moment of silence and then Sam took a long, wavering breath in, like he was gearing up to confess something big. Dean steeled himself against what might be the worst news of all: Maybe he wasn’t dealing with Sam any more. Maybe this was Lucifer.

“HUFFF-SHMPHHHH!” The blankets shook as the loud sound hit. The blankets on one side fluttered upward for a second. And then the blankets settled back down again.

Maybe this wasn’t a possession after all. Or, at least, not the supernatural kind. Dean put his knife away. “Sammy?” he tried again. “Can you come out?”

The blankets shook as rich, moist coughs sounded, though muffled through the layers of covers. Then there was a soft, weak, “D’n?”

“Hey. Yeah, I’m back.” Not knowing what else to do, Dean sat down on the very edge of the bed and laid a hand on top of the bulge that was his brother. He didn’t know what part of Sam it was—his side or maybe his back—but he rubbed in what he hoped was a comforting way. “You come down with a little something while I was gone?”

There was a soft, almost imperceptible sniffle, and the blankets shuddered again. “HUH-HURSCHPhhhhh!”

Dean had heard Sam sneeze hundreds if not thousands of times before. They were never small sneezes, even when Sam was a kid, which probably should have told Dean something way back then. But even though the covers Dean could tell these ones were different, stronger. Or maybe Sam was weaker this time around.

“Did-ya take something for this? Did Bobby give you some medicine?”

There was another grunt, but Dean couldn’t tell if that was a grunt in the affirmative or negative category. And before Dean could ask, the bed shook again with another sneeze. “HUH-WHUMPHShh!” And another. “HUF-SHUHPhhhh!” And another. “HUMPHSOOO!”

“You gonna come out and talk to me or stay in there and sneeze all day?”

“HUFFCHIPhhhhhhh!”

“Uh, Smamy? You got any tissues under there with you?”

There was no answer, and Dean rubbed two fingers against his forehead, starting to get frustrated. He stopped rubbing the blankets and ran his hand down to one of the blanket’s edges. Slowly, so he didn’t spook Sam, Dean lifted the blanket and peeked under. There was a lot of black. It was dark under there, and Sam seemed to be wearing a black sweatshirt, maybe his black hoodie. Dean saw a tuft of unruly brown hair and just a hint of skin, possibly an ear. But everything under the blankets shuddered. Then moaned. Then it came again. “HUHFMShhhhh! HURrrFschmphhhhh! Huh-huh-HAHHTCHMPHH!” The bulge under the blankets started shivering and wouldn’t stop. Shivering and sniffling. It shifted slightly, curling tighter in on itself, but still shivering. And sneezing. And whimpering.

 Dean lowered the blanket. Then he sat there, feeling helpless. He looked around the room. No tissue box by the bedside. No glass of water even. No bottle of Nyquil. Not even a blister pack of Aspirin. No one to sit with him. No big brother to look after him. Until now. “I’ll be right back, Sammy. You hold tight.”

A cough and not even a grunt this time.

Dean got up and headed back down the hall. He couldn’t get mad at Bobby. They were all doing the best they could right now in the shittiest of circumstances. But Bobby still should have called him back after leaving that voice mail that something was wrong with Sam. Even if Dean wouldn’t have been able to do anything over the phone except for worry, Dean still would have liked to have known what he’d be coming back to find. Dean wasn’t going to have words with Bobby, though. Dean only made it as far as the bathroom.

When he returned to Sam, ripping open the tissue box he’d found in the cabinet under the sink, Dean finally had a plan.

“Huhhh-WHIMSHhhhhh!”

Dean lifted the blankets again, this time along the side, and he carefully climbed in underneath. The not-so-little lump that was his little brother scooted over a little to make room for him as he moved in close, dropping the blanket afterward so it covered them both.

It was warm under the blankets. No, not just warm but hot. That was partly due to no fresh air though mostly because of a brother who was putting off heat waves so warm as if he were trying to compete with the sun at the height of summer. But Dean stayed close and, as his side pressed up against Sam’s, his brother moved—not to shudder again, but to come closer. He turned and pressed what was probably his face right into Dean’s chest. An arm came out and wrapped around Dean, holding him there as if scared Dean would leave again. Dean could see the curve of the black sweatshirt’s hood and of the sleeves. “I’ve got tissues here for you,” Dean said softly, fighting the urge to stick his head out and take a few gulps of the clean, cool air.

Sam sniffled loudly but into Dean’s chest. Then his body shook violently with an intake of breath and Dean knew what was coming. Damn it, why had he even bothered to get the tissues? Dean braced himself and put an arm around the warm but shuddering mass of Sammy. “huh… huh-huh-H’HUHPHSCHHUHHHHH!” Dean rubbed his hand up and down Sam’s back and felt Sam’s body relax against him as the shivering stopped.