He never would have bought the shirt himself.

He had grown up on hand outs and hand me downs, clothes given to them by well meaning acquaintances, or that Dean found for him mostly at yard sales or thrift shops.

Now that Sam bought his own clothes, he still mostly shopped in those places, not only because old habits died hard, but also because college was expensive and new clothes were a luxury he didn't really need.

He stuck with the familiar solid colors and lots of layers, plain t-shirts and broadcloth buttondowns that never went completely out of style, even if they weren't what the hipsters at Stanford wore, and hoodies because it rarely got cold enough to wear a heavy coat in California.

Jessica bought the shirt for his birthday, and for a moment he was taken aback before he remembered to smile and thank her and not hurt her feelings.

It was purple and had a dog on the front.

Sam didn't own anything purple. He honestly didn't remember if he had ever owned anything purple. According to John Winchester, purple was barely more masculine than pink.

Jess smiled and explained, that she had wanted to get him a dog for his birthday, that she knew he wanted a dog, but their apartment didn't allow pets, so the dog would have to wait until after they finished school and got their own place.

He understood then, that the dog shirt was a promise for the future, a future that didn't involve black dogs and vengeful spirits, a future that didn't include stitching your brother's back in a truck stop bathroom with dental floss for suture and cheap gin for disinfectant.

He wore the shirt that night when Jessica gave him his other birthday present, and while they lay in the dark afterwards, talking about what kind of dog they would get. Jess thought he should have something big and active, like a Labrador or a Weimaraner. Sam figured he would just go to the pound and find one that needed him.

The shirt went into his bag without a second thought when he left with Dean.

If Dean even noticed it that weekend, he didn't say anything.

It was the bottom layer, the shirt closest to his skin, when he came home after the weekend with Dean, which meant it was one of the exactly three shirts and one pair of jeans that he had to his name after the fire.

The week after the fire, Dean pulled the purple dog shirt out of the dryer in a laundromat in Nevada or maybe it was Utah, held it up, looked at it, and shrugged. He tossed it to Sam, and that was that.

A week later, the night after they left Lake Manitoc, he came out of the shower, reached into his bag for a clean shirt, and came up with the purple dog shirt. He sat on the bed and cried for two hours.

Dean poured almost half a bottle of Evan Williams down Sam's throat while Sam soaked his brother's shirt with tears and snot.

"I just want her back, Dean," Sam blubbered. "Even if I can't be with her, I just want her not dead."

"I know, Sammy," Dean whispered, stroking his brother's hair as he had when they were children, as the mother Sam didn't remember had done for Dean. "I wish I could give you that."

A wet droplet hit Sam's forehead and rolled down his face. Sam didn't look up, didn't embarrass Dean by acknowledging that his older brother was crying too.

Sam wore the shirt again two weeks after that, smelling homemade cookies and Jessica's shampoo and fabric softener in his mind even though he knew they weren't real, that the shirt really smelled like cheap detergent and the trunk of the car.

He wondered if his dad ever felt this way, if something made him miss Mom so much it was hard to breathe, but at the same time, grounded him into reality, reminded him that it was real, that it wasn't just a dream that became a nightmare.

He felt as if he had been kicked in the stomach when he realized that something was probably him and Dean.

He started wearing the purple dog shirt sometimes, but always under something else, where no one can see it except Dean. He knows other people won't understand and he doesn't want to have to explain if anyone asks that it was the promise of a future with a girl who will never have one.

Dean knew Jess gave it to him, and didn't say anything. But he didn't tease and bicker as much when he knew Sam was wearing it, either.

Sam was wearing the shirt when Dad finally called, and somehow, that seems fitting. Dad was on the trail of whatever killed Mom and Jess and Sam is going to help him, whether Dad wants the help or not.

They were close, so close, closer than they had ever been, to stopping the evil once and for all.

But then Dean was in trouble, and Dean needed him, Dean who was still alive, so Sam went back to Indiana to get Dean instead of going to California to find Dad.

He saved Dean from the scarecrow turned Norse god, but he couldn't save Dean from the rawhead, so he had to find someone who could. He spent days on the phone calling anyone he could think of, searching for a miracle everyone insisted could not be found.

But he spent his nights sleeping in the purple dog shirt, whispering to Jess that he hadn't forgotten, that he would avenge her death as soon as he could fix Dean, because he needed Dean's help.

Sam was training with Dean again and building up the muscles that had faded at Stanford. The shirt got tight, too tight to wear comfortably while they were on hunts, but at night he wore it like a hug from Jess, reminding him that he had work to do.

They found Dad, or rather Dad found them, but Dad left again, sending them to finish an old case rather than to track the demon.

Within a few weeks, Dad came back. Now they had a weapon, and a trail to follow.

Sam slept in his purple dog shirt and whispered to Jess that it wouldn't be long now, that he would end the thing that hurt her so she could rest in peace.

The trails turned bloody. Hunters died, even hunters the boys had known all of their lives like Pastor Jim and Caleb.

The deaths of more people they cared about didn't stop John, or even slow him down much. It just gave him more to avenge.

It all came to a head one night after they saved an innocent baby and her parents, in a motel room near Salvation, Iowa, while Sam was again wearing the purple dog shirt.

Dad went missing again.

Dad wouldn't or couldn't answer his phone, Dean was coming unglued, and Sam was livid that Dean had held him back and didn't let him go after the demon, even if it meant running into a burning building.

In the midst of the argument, Dean said the one thing that got through to Sam since the day Jess died.

"If hunting this demon means getting yourself killed then I hope we never find the damn thing."

Sam tried to argue, because this was The Demon, the one that killed Mom and Jess, the one they had been hunting their whole lives since they were way too young to even know what hunting was.

He lost his temper, because Dean just didn't get it.

Except that Dean did.

Dean reminded him that no matter what they did, Mom and Jess were gone, and they were never coming back.

Jess was at peace, as far as they knew, so killing the demon wasn't going to put her at rest.

Killing the demon would possibly save some other families from the heartache the Winchesters had survived, but sacrificing the living for the sake of the dead just didn't make sense.

That was the reason that when Dad said killing the demon came before everything, Sam quietly answered "No, sir. Not before everything."

The demon tried once more to stop them, hitting the car with a tractor trailer.

Sam sat beside Dean's bedside as the doctor gave the grim prognosis.

Dean was dying, and there wasn't much the doctors could do about it.

Dad, when he heard the news, was worried about whether the Colt was safe. He gave Sam a list of items he needed, the ingredients for a spell to summon a demon.

The two of them argued, and even though Dad promised not to hunt the demon until they knew Dean would be all right, Sam didn't believe him.

Sitting beside Dean's bed, Sam had hours to reflect on years spent with an older brother he was only now learning to appreciate. Sam had felt safe to pursue a future with Jess, the 9 to 5 job and the picket fence and 2.4 children and the dog, because he had always known Dean was out there somewhere. Dean would have watched over him. Dean would have laid down his life to give Sam his happily ever after with Jess.

But Jess is gone. That future will never happen. There won't be any blond, green eyed toddlers chasing a barking mutt while Jess tells them not to pull the dog's tail.

Jess is gone and Mom is gone, and nothing Sam and Dean ever do will bring them back.

In a hundred years, whether Sam ever got revenge for what The Demon did to Jess and Mom won't matter.

But if he could take a little of the evil out of the world, and save some people along the way, that would matter. It would matter to the people they saved, and to the people who loved the people they saved.

There was a strong possibility that some time in the next few days, if Sam couldn't pull another miracle out of the hat, Dean would be gone too.

Sam made a promise, sitting by Dean's bedside, that if Dean could just pull through, just breathe on his own and open his eyes and be able to get out of the bed, Sam wouldn't forget what mattered.

He would even try to fight with Dad less, because it upset Dean, but more so because he now understood how easy it could be to lose yourself in grief.

But it ended up that Dean came home from the hospital, and Dad didn't.

The brothers went back to Bobby's for a while, because whether he wanted to admit it or not, Dean needed some time to heal physically, and they both needed time to get their heads back in the game.

A month later, when Dean was scattered more than the pieces of the Impala in Bobby's garage, Sam asked Bobby if he could borrow a car to make a weekend road trip.

Dean's ears perked up like the ears of the dog on the purple shirt Sam didn't wear any more. He had known they would.

Dean announced he was going too, because even though Dean shouted to the heavens how he just wanted to be left alone these days, he wasn't comfortable with Sam out of his sight, as if Sam was going to vanish and leave him too.

They drove to California mostly in silence, and for once, Dean let Sam drive most of the way. They arrived in Kirkwood after dark and got a room for the night.

Sam didn't volunteer to talk, and Dean didn't press him.

The following morning, just after the sun rose and before most reasonable people would be out at a cemetery, Sam knelt in front of Jess' grave with a plastic pencil box in one hand and a gardening trowel in the other.

Dean muttered something about checking out the neighborhood and walked around reading the other headstones, while not so subtly watching Sam.

Sam dug a small hole and put the box in it, the box that contained his purple dog shirt, the keys to his and Jess' apartment, and his Stanford student id. He carefully covered the box, and laid the bouquet of daisies he had brought on top.

He whispered "Goodbye, Jess."

He stood slowly, taking one last look at her grave while he made a silent promise to her, to his father, and to the brother who now stood beside him, to never forget the living for the sake of the dead.

"Where to next?" Dean asked softly as they walked back to the old Challenger.

"Back to Bobby's," Sam shrugged.

"Don't you want to see anyone else while we're here?" Dean frowned.

"No," Sam shook his head. "I came to say goodbye." He opened the passenger door of the car. "Come on, we've got work to do."