A/n: Just something that popped into my head. So far I'm disappointed with season six, so it doesn't make much of an appearance in this. Oneshot. Set at the climax of 5x22 "Swan Song."

It's only one moment, but it feels like decades.

Dean watches his brother give himself up to the Pit, arms thrown back, hands splayed, like some sort of unholy sacrifice. Everything is blurred, made hazy by a combination of exhaustion and two soon-to-be black eyes, but the figure that is Sam is etched in high-definition. Dean freezes it in his memory, drinks in the familiar lines of his brother's jaw and his shoulders and his lanky, too-tall body, like he's drowning and Sam is the last drop of water in the desert.

And with that tiny part of his brain that hasn't completely ceased to function, Dean thinks of how far they've come.

He remembers Sam as a precocious toddler, a stubborn six-year-old, the second-grader who was too smart for his own good. He remembers fifteen-year-old Sam, angry and sullen and constantly fighting with Dad, and Stanford Sam, when Dean thought he had lost his brother permanently. The days they spent on the road together after Jessica's death are some of the happiest Dean can remember, even though Dad is missing, even though Sam is still grieving Jess's loss. For a while, things were okay.

And then, all at once, they weren't. Some part of Dean will never get over Cold Oak, will never recover from the sick, dead feeling of clutching his baby brother's lifeless body. It was the first time Dean ever really lost him, and he remembers the sharp tinge of desperation rushing through his veins as he struck a deal with the Crossroads demon, because he didn't know how to live in the world if Sam wasn't in it.

Dean remembers Sam's face as the clock struck twelve, his last moments before the endless barrage of pain that was Hell. Then he remembers getting out, the feeling that washed over him when he saw his brother's face for the first time—forty long years, almost half a century of pain and suffering, and when Sammy walked into the room it was like the first ray of sunlight after four decades of rain.

He remembers Ruby, and the demon blood, and the horrible feeling you get when you look at the person you once loved and barely recognize them at all.

And then he remembers how they got there.

He remembers Lucifer and Zachariah and Michael and Anna and hopelessness, that bitter feeling of losing faith in Cas, in God, in Sam. In life. He thinks of weeks of agonizing, of his brother's earnest face as he volunteered to jump into Lucifer's Cage and spent the rest of eternity as the Devil and Michael's scratching post.

And then he thinks, with an ache that makes his entire heart twist, of his own decision to let Sam go.

It's only a moment, but it feels like forty years. Dean remembers the events that got them to where they are now, of all the pain and heartache and death that has followed them their whole lives. He thinks of tiny moments spent laughing in some hick town, of prank wars that lasted from Missouri to Memphis, of sharing a cold beer on the hood of the Impala. He thinks of family and hunting and home.

But most of all, he thinks of Sam.

This is the last time he'll ever see his brother again. Dean feels as if he should say something important, something meaningful—he realizes he's never actually told Sammy the words I love you; he always considered it too mushy, a chick thing—but for this one instant, there is a hush over the entire world. A silence, and Dean can't think of a single thing he could possibly say that is worth breaking it.

And what does it all boil down to, in the end, he thinks. Love, family, brotherhood? Sure, maybe all of those things. Maybe there are a thousand different ways you could end their story, a thousand different words that could sum up what it means. Dean doesn't know any of them.

What he does know is that Sam is his brother, his family, and Dean doesn't know where Sam ends and he begins.

It's only a moment, but it feels like forever.

Sam and the Archangel fall into the pit.

Everything must come to an end.