Once when Sam was seven, he came home from school to an empty house.

The bus stop was only just down the street, and Dean had walked him to and from the corner a thousand times; so when there was no one waiting for him when he hopped the last step off the bus onto the curb, he didn't panic. He only glanced around once, cursory, before tugging his bookbag up on his shoulder and walking home. Fished the copy of the housekey out of his bag, from where Dean had attached it to a zipper with the steel split ring gutted off a keychain, and unlocked the door.

Sam had felt very grown up, and even rooted a snack out of the fridge for himself on his way to the bedroom he shared with his brother. Climbing onto the bed, and spreading out his homework and a textbook and the fruit cup, Sam glanced at the wall clock and thought, He'll be home soon.

After two hours, all his homework done and packed away again, the youngest Winchester felt the first cold nudges of fear. "He'll be home soon," he told himself firmly, and went to the kitchen to throw his empty fruit cup away, even washed his spoon. Wandered around the house sort of tidying up where he could with their meager belongings, did his best to ignore the clock that seemed to be ticking louder now, because it was dinnertime, wasn't it? And he was all alone.

He ended up going back to his room, picking a book off the shelf and searching for the dog-eared page. Smoothing the fold back out with trembling fingers, Sam blinked stubbornly through tears and started to read.

Four chapters later, and the front door flew open so hard it cracked against the counter. Sam started, jerking his head up, and heard the heavy thud of his father's boots.

Instantly uneasy, fingers bending the paperback spine a little as his hands curled with fear, Sam flinched when he heard glass break somewhere in the house, and scrambled off his bed to slide underneath it. He reached out as an afterthought to drag his bookbag under with him, and huddled there to stare past the edge of the blanket at the doorway. His heart thumped against his breastbone so hard he thought one or the other might break.

He saw his dad's feet come past the door, pause, step in- and Sam clenched his eyes shut tight, covered his mouth with both hands, and stayed still, until his father turned away again and left the room, thumping through the rest of the house like some kind of lumbering monster.

And he had stayed in his spot under the bed for a long, long time after that, long after the front door had slammed shut and he heard the car roar away. He stayed there with his hands clenched in front of his face, crying because when Dean was there it was okay, but Dean wasn't and Sam was alone and he was almost alone with daddy, and-

He's scary, Sam realized that day, the only sounds in the whole house his muffled sobs and the ticking clock. Daddy's scary.

The front door had opened again and Sam froze, eyes wide.

"...has to be here, Bobby, he has to. Sam? Sammy?" The steps that moved through the house now were hurried, and the voice calling out was frantic but familiar. Sam scooted out from under his bed just as Dean appeared in the bedroom doorway. "Oh, thank god."

There had been something wrong with Dean's face- it was mottled on one side, weirdly yellow and purple- but Sam was so shaken that all he could do was bury his face in his brother's wet jacket and cry and cry.

"I'm so sorry, buddy." Dean's arms around him were warm and solid, the only constant left in the whole entire world. "I'm sorry, Sammy."

Two days later, he was sitting on the steps of Bobby's wooden porch with a cream soda, one of the salvage yard dogs, and his very first cell phone. It was a ten dollar tracphone from the supermarket; Dean attached it to a Batman lanyard so Sam could wear it around his neck, and spent whole hours teaching him how to use it.

"Here's my number, see, Sammy? It's lit up red all the time, so people will know to call me if there's an emergency. And here's Bobby's, too. From now on, if you're ever alone or scared, this will keep us together. You can call me, and I'll come find you, no matter what."

And Sam had kept it close every day; plugged it in next to his bed very carefully every night, and hung it around his neck every morning. Dean was with him the next time they saw dad, back at that little house, but Sam's hand still flew to the phone at his chest the moment dad walked in. He had clutched it with fingers that shook even as Dean rubbed a hand through his hair.

Sounding really sad when he said, "That's okay. You hold onto it, Sam."

"...am. Sam? Hey, are you okay?"

Sam started, jerking his head up. The class was splitting into pairs to start work on the last paper of the semester, and Ava was turned around in her seat, brow furrowed in concern. It took Sam a moment to realize he had his phone out on his desk, and both hands curled around it tightly.

"Oh. Oh, I uh- " He stuffed it back in his hoodie pocket, blinking. "Sorry, I guess I zoned out."

She studied him for a minute, then smiled and plopped her folder down on his arm."I'll say. Anyway... "

Sam shifted through the papers as she talked, reaching down to his bag to pull out his notebook, one hand curled resolutely around the security blanket he never grew out of.

Three days later, Dean was a bundle of nerves when Sam slid into the front seat of the Impala after school, fingers drumming on the steering wheel in the biggest tell Sam had ever seen. The middle child blinked at him, and then twisted around to look at Adam; who shrugged his shoulders, eyebrows cinching up to meet his hairline.

"Dean?" Sam finally said, reaching out to poke his shoulder. "Hey, man, what's wrong?"

For a minute it didn't look like he would answer. Then he leaned forward and dropped his face on the wheel and groaned. When he spoke his words were so muffled Sam had to strain to catch them.

"Letter should be in the mail today."

"Letter?"

A barely perceptible nod, and Dean didn't lift his head. "From school. Final scores."

Sam blinked once, twice; then his mouth dropped open and his eyes widened pretty much on their own. "Your final scores? You're done? You graduated?"

The sound his big brother made was as close to a whimper as Sam had ever heard out of him. "Unless I failed everything."

"Oh my god, Dean." Sam shoved his shoulder, a grin threatening to split his face in two. "Hurry up and drive, the mailman totally should have been there by now! Let's go! Tell him, Adam."

"Let's go, Dean!"

Dean's expression was pathetic, but he started the car and pulled onto the street regardless. Sam watched him sidelong, trying to bite down the corner of his smile so he wouldn't start gushing, because damn.

Dean was incredible.

"Cas!" Adam called as soon as he popped open his door, and Sam got out and shaded his eyes to look in the direction Adam was scampering. The blue-eyed man was waiting by the parking lot gate, and held up his hand in response to Sam's cheerful wave, already bending to catch Adam's signature football-tackle-hug.

"Adam, jesus," Dean said without heat, shouldering the grade schooler's bookbag and meeting Castiel's eyes for all of two seconds before his gaze shuttered away and he reached back to tug the gate closed behind him.

Sam snagged Adam by the sleeve and dragged him out of the way as Cas stepped forward to put himself in Dean's way. And when Dean had absolutely nowhere else to look, Castiel put his hand on Dean's shoulder. It looked like nothing but the barest press of his palm into Dean's collarbone, and somehow a thousand times more intimate than an embrace.

When Cas smiled, tension Sam hadn't even noticed melted out of Dean's shoulders, and Dean smiled back.

"Hey, Cas."

"Hello, Dean."

Sam wrapped his arms around Adam's shoulders and propped his chin on Adam's head, grinning ear to ear as his little brother giggled. Dean glanced over on autopilot at the sound, and at the same time his eyes softened on the two of them, his face folded into an annoyed scowl.

"Brats. One of you grab the mail."

He tossed his keys over and Adam caught them, scrambling through the front door and over to the row of mailboxes in the lobby. Sam stepped back to keep an eye on him through the glass of the door, and wasn't watching when Castiel said, "I'm certain you did wonderful."

And he wasn't watching when Dean muttered, "I don't do wonderful."

Adam came bursting out the door again, with a handful of envelopes he ran over to Dean. When Dean shuffled his school letter out first, a thick white envelope, he passed the others over to Cas. Castiel took them gravely, and even though Sam knew Dean did fine, he was still holding his breath as Dean ripped open the evelope along the side and drew the letter out lengthwise.

Dean stared at the page for a long time, and when it was obvious he wasn't reading anymore, Sam inched forward to pluck it out of his hands. With Adam pushing against him on one side, and Cas leaning over his opposite shoulder, Sam read, "Congratulations," and "3.8 GPA" and "degree will conferred at graduation ceremony," and that's when the page started swimming.

"Oh my god, Sammy, you're such a girl."

"Shut up, you jerk." He rubbed at his eyes with his sleeve before he could actually start crying and let the letter go when Castiel drew it away. "You're gonna graduate. You finished college. Dean, you're twenty-one, that's- incredible."

My big brother, he thought fiercely, is incredible.

Castiel smiled warmly, fingertips tracing what Sam could guess was the Dear Mr. Dean Winchester at the top of the page.

"Wonderful," the man murmured like it was a conviction, and Dean flushed.

"Yeah, it is," Adam concurred, blue eyes round and serious. "And we're gonna be proud of you whether you like it or not, so take it like a man."

Sam drew his phone out and found Ellen in his contacts. Dean had a shift at the Roadhouse tonight, but surely Ellen would understand if he was just a little late today. They had to celebrate. Dean worked so hard, and it was finally starting to pay off; and Castiel didn't look inclined to leave any time soon, gazing as fondly at Dean as if they'd known each other for years. Sam wanted Cas to come celebrate with them, too.

Just a quick dinner somewhere nice. That wasn't asking too much, Dean easily deserved that.

So he started a new message thread and sent her a quick text.

"Hey, Ellen. So get this."