A/N: Season 9 is really great and painful! I am getting frustrated with Sam at the moment (though I love him as always) because of the hard line he keeps drawing with Dean. After watching 9x12 and 9x13, this little scenario popped into my head.

Usual disclaimers apply.

Title is from the Fellowship of the Ring song "In Dreams"

Sam gets some sleep, because that's what he said he was going to do.

He's a man of his word these days.

He wasn't always so certain, so practical.

He wasn't always able to sleep. He remembers the nightmares and the visions and the misery, the indecision and the feeling of being lost, the searching and the wondering.

The rock of knowledge in a stormy sea had always been that Dean was there.

It's all changed.

He keeps his dreams as carefully controlled as he does his words to his brother—cold, austere, stony.

He knows he's dreaming because even though he feels wholly awake in this vast room of his own making, he's not alone.

"What the hell are you doing in my dreams, Cas?"

Castiel blinks. "Your brother always says the same thing."

"Wow. Really? So this is like, a tradition? Winchester dream invasion?"

Cas doesn't answer. He's pacing the ground, pondering something. As he does. Then—"Your dreams are darker than your brother's."

Sam scoffs at this. "I find that hard to believe."

"Dean's dreams are...disturbing, on occasion," Cas admits. "But mostly he dreams about his family."

The edge on the last word is not lost on Sam. "Get out of my dream, Cas. We're not talking about this."

'This' being, as they both know, what Sam said to Dean. Words not so much like the stabs of a dagger, quick and unpredictable and messy...more like the thin, practiced cuts of scalpel, deliberate, precise.

Straight to the heart.

"Your brother is hurting."

Cas sounds more mournful than judgmental. That, Sam reflects, is one of the most frustrating things about the angel. He has done some pretty messed-up crap, but there's still such a pure innocence about him.

"I know that I have messed up crap," Cas says, a bit self-consciously, and Sam realizes that it's a dream, and his inner reflections are out in the open.

He thinks of saying sorry and decides to say instead, "Yeah, well that's what you get, snooping other people's brains."

Castiel ignores Sam's trademark snark, choosing instead to sit down on the flagged stone floor, back pressed against the cold granite wall. "Why would you create this room?"

"It's just a dream."

"Dreams are important."

"Why are you here?" Sam's annoyed, because he feels little hairline cracks of doubt beginning to fissure the smooth rock surface of his dreamworld (of his heart) and he doesn't like it.

Castiel raises his eyebrows and his shoulders in some sort of ultra-shrug. "I—some part of me hoped that I could help you and Dean...reconcile. You're my friends. It pains me to see you split apart."

"That boat's already sailed," Sam says with a sigh. He sees Cas's eyes brighten and adds quickly. "There's—not an actual boat, Cas."

Castiel looks crestfallen. "Ah. It is a...turn of phrase. I understand." He looks regretful. "Like the guinea pig."

There's a pause.

"Yes," Sam says. "Like the guinea pig."

Cas splays his hands against his knees and meets Sam with a dead-on stare. "I wish you had a real guinea pig, Sam. They are marvelous creatures of the Lord."

"I thought we were talking about my failings as a brother."

"Yes." The sarcasm of Sam's remark is lost on Cas. He doesn't understand sarcasm, Sam knows, or maybe he doesn't care to.

Sam walks the length of the dream-room and then spins on his heel to look at Cas. "Well?"

"You and your brother should not be at odds." Castiel looks almost childlike, sitting against the wall with his long legs stretched out in front of him. "He loves you, Sam."

"Dean betrayed me," Sam growls, feeling the raw edges of his anger (grief) creep into his voice, and hating himself for it.

Cas considers this sorrowfully for a moment, then switches back to his usual earnest urgings.

"What he did was wrong. But we've all messed up the world, Sam. You're not supposed to cheat death; nobody is. Imbalancing the scales of the universe does bear a terrible price. But even in his mistake your brother was willing to pay that price."

"He's still selfish," Sam argues. The words echo hollowly in the stone room.

"Everyone's a little selfish," Castiel accedes. "But your brother is...less so than most. All he wants is family."

"Well we don't get that! We don't get to have family. And it's Dean's twisted quest for it that ends up in bloodshed and misery, every damn time!"

Castiel looks pained. "I didn't say he was faultless," he says, very softly. "But family's important. Family means having something to lose."

"And why would I want that?"

"Because it also means having something to fight for." The angel's eyes are almost painfully bright. "That's what keeps your brother going, Sam. And even though you do not wish to admit it, it keeps you going too."

Sam doesn't know quite what to say to that, and he doesn't like not knowing. So he switches the line of the conversation ever so slightly. "Yeah, the whole because-we're-family crap. That's rich, coming from you. You know damn well how screwed up my family was! I'm just the only one to recognize it for the problem it is, to step outside the goddamn stupid dynamic."

"You're not the only one," Cas points out mildly. "Your father did the same thing, business over blood. You used to hate him for it."

Sam feels something cold twist in his gut, colder even than the frigid temperature of the dream-room. "I am not my father."

"No, you're not," Cas admits. "Though he wasn't a monster. Neither of you are. Because Dean wouldn't let that happen."

Sam is silent. It's his head, his dream, his decision—but he doesn't feel like he knows the answers anymore.

Castiel stands up and faces him. He has to look up, because he's shorter than Sam (everyone is) but the steely blue of the angel's stare is no less intimidating.

"Dean gives you everything he has. He always has. And that counts for something, even if it sometimes it makes matters worse."

"Sometimes? Try always." Sam shakes his head. "I just don't get why the hell he does it."

Cas sighs. "Because it is all he knows how to do."

The silence is heavy between them. Then Sam whispers, "Get out, Cas."

And just like that, the room is empty.