Dean's eyes saddened at that, mostly at the brave smile than the words, and he just couldn't help petting Sam's hair a bit more. God, Sam was still just a child to him, and despite always saying their father raised both of them, they both knew Dean did most of the work raising Sam and no one could take losing someone this close and important to them, especially not a Winchester.
"Dammit, Sammy," he breathed out, just helping keep Sam comfortable for the last few moments. It'd be any minute now, and he could tell the army would be readying themselves. He didn't even want to think about any of this war anymore.
Reaching to rub away some of the tears on his face, Dean let out a shaking sigh, looking over to Red. Every bit of this hurt every time he saw his brother die and he didn't even get to go with him this time.