After Jessica's death Dean expected Sam's nightmares. He had them too, after Mom died. He'd wet the bed, wake up sobbing, screaming for his Mother. Dad, who got mad about so many things, never got mad about that. He'd change Dean's pajamas, tuck him into the big bed, and mumble reassurances into his hair until Dean fell asleep again. More often than not, Sammy, who had been a poor sleeper since he was born, ended up in the big bed as well. Some nights, Dean didn't have a nightmare, but his Dad did. He'd wake up screaming for Mom, and it sounded so much like that night that Dean would shoot out of bed, heart pounding. He'd crawl into Dad's bed on those nights too, but instead of reassurances Dad would whisper apologies and hold Dean so tight it hurt.

And that's how the three of them made it through that year, clinging to each other.

For about 10 years after that, Dean would wake up to find that Sam had crawled into his bed. When he was really little, he would push his entire body into Dean's and they would wake up in a confusing scramble of limbs. It happened less and less as Sam got older. Soon he'd only curl up against Dean when he was sick or had a particularly bad nightmare. At 8, he had proclaimed himself too old for cuddles, but he would still crawl into Dean's bed when Dad was away on a hunting trip and they were left alone to wait and wonder.

Those nights Dean would turn on the TV or read aloud from their meager collection of comic books or, if Dad was gone longer than he said and the countdown to calling Pastor Jim was on, he'd whisper that everything was going to be ok, told jokes, did anything he could to wipe the look of pure fear off of Sam's face.

Now, they were grown men. They handled things differently.

At first, Dean ignored Sam's nightmares.

Long instinct meant that he woke up the moment Sam's breathing sped up. Sam would mutter Jess' name over and over again until he finally shot up in bed with a loud gasp.

Dean pretended to be asleep. If Sam was thinking about it, he wouldn't be fooled. Dean slept so lightly that Sam hesitated to go to the bathroom in the middle of the night because he knew the light under the bathroom door would wake Dean up. But Sam wasn't thinking about it.

He was thinking about Jessica in the fire. He'd sit awake with his head in hands until he fell back into an uncomfortable sleep or morning came.

But Dean pretended not to notice and Sam let him pretend because that's how one share's space with an adult brother, that's how once creates privacy.

But the nightmares got worse instead of better.

Sam woke screaming, then vomiting, and Dean couldn't ignore that.

The next night, when Sam's panicked breathing started, Dean sat down on the bed beside him and put a hand on his shoulder.

"Sam – Sammy wake up."

Sam woke with a gasp.

"It's OK, you're dreaming," Dean said, trying to keep his face impassive, to betray no real concern, just annoyance.

Sam ran a hand over his face and muttered an apology.

Dean didn't know what else to do, so he just said it was fine and went back to lie in his own bed. Both of them clearly still awake.

"Wanna talk - "

"Nope."

Dean sighed but didn't push. They hadn't been together long enough. They had fallen into most of their old patterns easily, but there were other moments where it was clear their landscape had changed. Dean was having one of those moments when he looked at Sam and all he could see were the walls had been put up, secrets buried, holes in their knowledge of each other.

The next night, Dean put the TV on, but it didn't put Sam to sleep like it did when they were children. He would just stay awake watching infomercials and MASH reruns and Dean didn't know if that was better or worse than falling asleep.

Dean stopped with the TV and tried driving the long way, hoping that the familiar purr of the Impala would lull Sam to a peaceful sleep. It didn't. Sam still woke up screaming. The only difference was that Dean almost crashed the car.

Then they took down Bloody Mary and Sam spoke with Charlie. There was a moment, when they drove away, when Dean thought that would fix the problem. It didn't.

Sam woke up two nights later. The nightmare had been one of the bad ones. Sam woke sweating and screaming then disappeared to the bathroom. Dean lay in bed listening to him vomit feeling wrong – it always felt wrong the watch Sam struggle and do nothing – thinking about Sam's words after Bloody Mary.

I'd die for you.

It was a surprise to hear this stated, with so little fanfare, like it was a fact Sam knew with as much simple certainty as his own name. Sam would die for him, Dean would fix this problem for him.

The next time when Sam woke up with Jessica's name on his lips Dean started talking. Not about anything in particular, about hunts Sam hadn't gone on, places he wanted to see, and movies he wanted to watch. The words were light and airy and soon they carried Sam back to sleep.

The next night, Sam woke screaming again and Dean started talking himself hoarse. He talked Sam to sleep again and again. His own tiredness was starting to make him irritable. He felt for his brother, he did, but tomorrow he was sleeping in the Impala. He was -

"Hey, Dean," Sam muttered, his eyes-closed, half-asleep. He looked like a ginormous child "Thank you."

Dean didn't know Sam would sleep through the night a few days later, that the nightmares would decrease and then change. In that moment, he just knew that he would do this every night for the rest of their lives if that was what Sam needed.

Sam no longer crawled into Dean's bed crying about monsters under the bed, but he still needed Dean and that was all Dean needed, that was the true north he had been missing these past few years.

I'd die for you.