Disclaimer: Not mine.

Author's Note: The tags are back! ;-)

Many thanks to Cheryl for the quick beta on this. And to everyone who read the last tag months ago and is still sticking around to read this one.

Summary: The boys straighten things out. Tag to 9.12, Sharp Teeth.

A Matter of Trust

"Sammy?"

"It's Sam."

The words hadn't been spoken with anger – Sam hadn't even raised his voice – but Dean still flinched. It's Sam was what Sam told random people they met if they ever heard Dean addressing his brother as Sammy and assumed that it was a universal privilege. It was what he told people he was working with.

Apparently Sam hadn't been kidding.

"Sorry. Sam. I need to ask you something."

"Yeah?"

"You said Gadreel left… some… grace… in you?"

Dean kept his voice as neutral and non-accusatory as he could. There was no point pissing Sam off more, and in any case whatever Gadreel had or hadn't left behind when he'd been ejected wasn't Sam's fault.

"Yeah, he did. It's gone now."

"Gone?"

"Yeah, Dean. Gone."

"How?"

Sam gave a put-upon sigh which, perversely, made Dean breathe a little easier. Sam being sullen was far better than Sam treating him as a polite stranger. Sullenness meant he at least still cared enough to be angry.

"Cas took it out."

There was something wrong with the way Sam said it, like he wasn't happy with Castiel about that. That made no sense. Sam was the last human being on the planet who would want Angel bits in him, and Dean was including himself in that list.

"There's no grace in you now. That's a good thing, right?"

"What? Yeah, of course. I didn't want it in me."

That sounded genuine enough.

But Dean knew he hadn't imagined the hint of displeasure in his brother's voice earlier.

"So," he asked, feeling his way carefully, "we're pissed at Cas why?"

"I'm not pissed at Cas," Sam muttered. "I have no idea why you would be."

Dean felt like banging his head on the nearest convenient wall. He'd forgotten what a frustrating little bitch Sam could be when he dug in his heels.

"Clearly you are," Dean said evenly. "If it's just because he messed up your filing system then I don't care, but if he hurt you then I need to know about it, Sam."

"We discussed this. We're just working. We're not –"

Sam cut himself off and turned away. Dean felt a sudden flash of anger. He wasn't denying that he'd screwed up, and if Sam wanted to take a couple of swings at him he'd stand there and take it, but nobody, nobody,got to tell him that he had no right to look out for his little brother. Not even his little brother.

"Sam!" Dean snapped, reaching for his brother's arm to turn him around.

Sam didn't turn it into a fistfight. Dean had been half-hoping he would; it would let them both work off some of their frustrations.

Sam didn't turn around, either.

He just stood there, all twenty feet and eight hundred pounds of him, firm and unyielding.

Dean hadn't realized how much Sam let him push him around until he was standing in the middle of the library tugging fruitlessly at his brother's arm. Sam didn't budge, and Dean could probably use stronger force but he felt like that would be crossing a line they couldn't come back from.

Hell, he didn't know if they could come back from the lines that had been crossed already.

"Look, I get it," he said, and it felt like was ripping his own heart out. "You don't need me to be your big brother. Fine. I'm not pushing you on that. But if we're working together, then I need to know what's wrong before it comes to bite us in the ass."

Sam shrugged. "It's nothing. Just… We could've used it to find Gadreel."

"The grace?"

"Yeah. There's a tracking spell."

"But it's gone, so we can't?"

"We tried." Sam shook off Dean's hand and turned to face him. "Cas… extracted some of the grace. I told him to get it all but he didn't. He said it would… you know…" Sam trailed off.

"No, I don't know, so how about you tell me."

Sam rolled his eyes. "He said the extraction process would kill me if he went on so he stopped, and what he'd got by then, it wasn't enough to track Gadreel. Then when he healed me the rest of it vanished."

Dean considered that. Sure, it would have been good to track Gadreel, but it wasn't Cas's fault that he hadn't been able to extract enough grace for that.

"So… why are we pissed at Cas, again?"

Sam looked at him like he was speaking Mongolian. (Dean thought Sam couldn't speak Mongolian. He wasn't entirely sure, though. With Sam Winchester it was best not to bet too much on what he didn't know.)

And then a horrible thought occurred to Dean.

"You said he healed you – did it hurt you taking it out?"

Sam looked bewildered, but he answered. "It was like just after the trials – in the church. I couldn't… Cas said my body regressed."

Oh, now Dean got why he was supposed to be mad at Cas. All this, lying to Sam and tricking him and letting Gadreel possess him, and now Sam deciding he didn't want to be Dean's brother, all this to keep the kid alive and Cas had risked it for some stupid spell that he wasn't even sure would work?

"How bad?" he demanded.

"What?"

"How bad was it, Sam?"

"Oh… I don't know. Bad, I guess. There was blood. It was a bitch getting it all off the floor." Sam shrugged vaguely. "I did try telling him to go on but you know what a stubborn ass Cas can be."

For a minute or so Dean's mind was stuck on there was blood on the floor and all the mental images that came with that, and then he registered the second part of what Sam had said.

"You told him to go on?"

"Well, yeah."

Sam was saying it like it was the most obvious thing in the world, and the last time Dean had felt this mixture of horror and terror and disbelief had been in that church trying to talk Sam down from the brink, and all the pieces were falling into place like parts of some twisted jigsaw puzzle.

"Why?" he whispered, praying he was wrong.

"Because we need to get to Gadreel. You want to get to Gadreel."

"So." Dean took several deep breaths. He shouldn't shout. Shouting at Sam was counterproductive, especially when Sam was sulking at him anyway. "So. You're pissed at Cas because he stopped when it was getting dangerous for you instead of going until he had enough grace to track Gadreel."

Sam looked at him like that should have been obvious.

"You think" Dean went on, just to make sure he hadn't misunderstood, "I'm going to be pissed at Cas because he stopped instead of going on until he had enough grace to track Gadreel."

"Dean, I know you want him – I know you want revenge –"

"Shut up, Sam," Dean got out, pushing past his brother to go to his room.

He couldn't – couldn't – face Sam right then. He couldn't deal with the fact that Sam seemed to think Dean's priorities put some stupid Angelic tracking spell over Sam's wellbeing.

He paused in the doorway.

It still sucked that Sam had so little faith in him, it still hurt, but walking away had never managed to solve anything before.

"Sammy?" he said, not turning.

"It's –"

"Sammy."

"What?" Sam snapped.

"You're a moron."

Dean spun on his heel, walked the two steps to Sam, seized his wrist and pulled him towards the table. Sam was startled enough that he came, which was just as well because Dean wasn't as young as he used to be and it had been a long day and he was so not up to pushing Sam anywhere if he decided to resist.

"Sam," he said firmly, because they were going to deal with this immediately and that meant not letting Sam talk him out of it, "we're going to sit here, and we're not moving until you've explained to me exactly why you think revenge is more important to me than your life."

"Screw this." Sam pulled away from him. "I'm done with this, Dean. Whatever your angle is this time –"

"What the hell are you talking about? I'm not playing an angle!"

"Like hell you're not. This is just another thing, right? Like asking me trust you in the church. Asking me to trust you when you tricked me into letting Gadreel in. Whatever you want this time –"

"I was a dick about Gadreel, Sam, and I admit it and I'm sorry, but what the hell do you mean the church?"

"If you'd just told me why you needed me alive –"

"What the hell? What, are you stupid all of a sudden? I need you alive because I need you alive, Sam!"

"Don't lie to me, Dean. I swear I will be gone if you –"

"What exactly do you think I'm lying about, Sam?" Sam scowled, and Dean honestly didn't know what he was supposed to say. "Sam. Seriously. Help me out here. What do you think I'm lying about? You're my little brother. There is nothing, nothing, in the entire goddamn world that's more important to me than –"

"This," Sam interrupted. "See? This. Just like last time. You want me to do what you say, so you make up some crap –"

"You think I'm making this up?" Dean wasn't sure whether he wanted to shake Sam or check him for possession. "Seriously, Sam? You're my brother! I know we've had our differences, but –"

"That's what you call it? Differences?"

"Oh, come on, Sam! It's not like you've never screwed up –"

"No, I did screw up with the demon blood. And you held it against me for years. You're still holding it against me." Sam pushed his chair back from the table. "You know what? I'm done talking. You wanted to work, we can work."

"Sam!" Dean said as his brother went to leave the room. "You remember how it went with the demon blood thing?"

Maybe it was his tone, maybe the fact that he wasn't yelling this time, but Sam paused and turned back. "Really? We're going into that again?"

"Why did you do it?"

"Dean –"

"Just answer that one question, Sammy. Why'd you do it?"

Sam bit his lip. Dean waited.

Finally, with a grimace, Sam said, "Because I didn't know how else to save you."

Dean let the silence stretch for a moment before he spoke. "I'm not saying you have to forgive me today, Sam. I lied to you and I tricked you. And I can't even promise I'll never do it again. I'll try not to, but if it's your life in the balance then all bets are off. And at some point I'm pretty sure you're going to lie to me, too, like about all those things you delete from your browser history –"

"Dean!"

It was bitchy and pissed off and Sammy. Dean laughed. "So, yeah, we're going to have problems, and we're probably going to be pissed at each other and I'm pretty damn sure we'll get into a few fistfights. But I'm telling you the truth now. You're more important than revenge, more important than hunting, more important than anybody we know, more important than the entire damn world. There is nothing and nobody more important than you are. If you ever make me say this again, I'm going to feed you greasy burgers for a month. Got it?"

Slowly, Sam nodded.

"Good. Now… Are you going to make me wait years before you forgive me?"

Dean heard the fear creeping into his own voice, and although he hated it, he couldn't do anything about it. He needed Sam's approval more than Sam had ever needed his, and he didn't know –

"Garth was right," Sam said abruptly.

"Garth? What's Garth got to do with anything?"

"He said I had insecurities. For good reason."

Dean scoffed. "What the hell are you insecure about?" Sam met his eyes and glanced quickly away, and Dean's breath caught. "About me? Come on, Sam –"

"You've never trusted me." Sam's voice was low and tight, like he was fighting not to cry, and it took all Dean had not to grab him. "I want to trust you, Dean, I do, but I don't know how when you won't trust me enough to let me make my own decisions."

"Sam, you know how sometimes you know something's wrong, but you do it anyway because the alternative's something you can't even bear to think about?" Without waiting for an answer, Dean went on, "Well, that's it. I can't watch you die. I – I can't even make promises, Sam, because I guarantee that if you're dying and there's something I can do to save you, I will do it no matter what it costs. Even if it makes you hate me."

"I don't hate you."

Dean supposed that was something.

"So… We good?"

Sam shrugged. "I need some time."

This time Dean didn't stop him when he got to his feet. He turned away, not wanting to watch Sam leave the room. It was stupid, considering that Sam was just probably going to his own bedroom, but it still felt like Sam walking away from him.

When the door shut behind Sam he let himself break down.

He couldn't help it. He hadn't thought it was possible – all through their conversation he'd been waiting for Sam to laugh and tell him he was forgiven – but apparently he'd done the impossible. He'd screwed up so badly that even Sam, the baby brother who'd once all but worshipped Dean, bleeding heart Sammy Winchester who got teary-eyed when he saw ASPCA ads, couldn't find a way to forgive him.

He supposed it had to have happened eventually.

He didn't even know if he'd gotten through to Sam or if Sam still thought Dean considered some stupid spell more important than his brother's wellbeing.

And all of a sudden he found himself not caring about anything else. Cas and Crowley and Abaddon and Cain, what the hell did any of it matter? He wasn't going to be able to talk Sam down from any more brinks – he'd made sure of that with his stunt with Gadreel – and the way Sam was going, he was just looking for a cliff to throw himself off.

Dean went for the liquor cabinet.

A couple of hours, he realized he'd just made it worse. He still felt miserable about Sam, and he'd actually managed to get himself drunk enough that he was going to have a killer hangover. At least Sam hadn't seen him; if he could get himself to his room, he might escape the worst of the lecture.

Of course, that was assuming Sam cared enough to lecture him.

Maybe Sam wouldn't even care enough to tell him about his arteries the next time he got a hamburger. That should've made Dean happy; he could finally eat what he wanted without having to explain himself to his kid brother. Instead it just made him feel… empty.

It was the small hours of the morning by the time Dean managed to stagger to his bed and pass out.

Less than an hour later, he was in the bathroom throwing up.

What was left of the night was miserable, and Dean spent most of his time stumbling up and down between his room and the bathroom until Sam came in to brush his teeth and found Dean curled up against the bathtub shivering.

Oh God. Just when Dean thought it couldn't get worse.

"Please go," he choked. "Just – don't leave, that's not what I mean – but please go."

He didn't hear what Sam said in reply, but a moment later he was being manhandled to his feet and down the corridor and then he was sitting at the library table wearing Sam's hoodie and clutching a cup of coffee.

"You're a moron," Sam announced, dropping into the chair next to him.

"Please don't sugar-coat it," Dean muttered.

"Dean. There was absolutely no reason to try to give yourself alcohol poisoning. When I said I wanted time I just meant… You know, a few days or something. I'm not saying – I was pissed, and I am pissed. About Gadreel, yeah, but you just took off after that. You didn't even stay to try to fix things. Like it didn't even matter to you –"

"I couldn't," Dean said, hating the way his voice was starting to shake again. "I couldn't stay and find out you hated me –"

"Haven't we been through this? I don't hate you."

"– and I know you – you stayed after the demon blood thing and I threw a lot of crap at you and you took it, but I can't. I'm not – I've never been that strong. It wouldn't matter if it were anyone else, but… not you. I can't handle you… not trusting me."

"All right," Sam said, sounding surprisingly not angry. "Then give me a reason to trust you."

"You can pick the music?" Dean offered. Sam rolled his eyes, but the slight upward quirk of his lips told Dean he might be getting somewhere.

Abruptly, Dean stuck out his arm, pulling up his sleeve as he did.

Sam looked down at the Mark of Cain.

"I had to prove myself to get this," Dean said, looking Sam in the eye. "I had to prove I'm a killer. And Cain said… there'd be side effects."

"What kind?"

"Not the good kind. But no specifics."

"Anything yet?"

"Nothing. I killed two demons to get it. Worked with Crowley. He's searching the bottom of the sea for the knife now."

"OK. So –"

"I told a bartender about you after I was done with Cain. I was broody and she wanted to know why and I said my baby brother was mad at me. I was kind of drunk."

"Dean –"

"She said maybe you didn't deserve me. I told her she didn't know what the hell she was talking about. And then I didn't call her even though she gave me her number."

"Dean –"

"Crowley said he'd been in your head and that made us family and I almost decked him. I'm sorry I had to let him in your head, but I had to get through to you… And you need your tattoo back, why haven't you had it done yet?"

"Dean –"

"We'll get it done. I know how much you hated it last time and it'll probably be worse now. I'd do it for you if I could but I can't draw and –"

"Dean."

Dean blinked at his brother. "Yeah?"

Sam leaned forward and hugged him.

Dean swallowed. Apparently Sam wasn't going to make him wait after all.

"Sam?" he whispered.

"You can call me Sammy."

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