Even soulless, Sam felt just the smallest flicker of pain as he watched his brother through the window, standing on the far side of the street hidden under a shadow. Watched him smile and laugh with Lisa and Ben, but he knew, he recognized the expression on his face. The same look he'd had when their Dad had died. Trying to stay brave, keep a forced smile, but his eyes betrayed it all.
With a sigh, Sam leaned his head sideways against the pole beside him, gazing through the window at Dean. His brown eyes gently studied his older brother's face. He looked like he'd been crying, and his hair was still slightly messed up, but he wasn't the bloody mess he had been when Sam last saw him. In fact, he seemed somewhat happy. As he watched Dean, seated at the table talking to Lisa and playing with Ben, it was the most normal that Sam had ever seen his brother at all. Maybe not the happiest, but he looked... Free.
Sam couldn't help it. Even soulless, he felt a twinge of jealousy deep down in his stomach. Not jealousy for Dean, but for Lisa and Ben. Jealous they had Dean now, and Sam didn't. Jealous that now Ben would.. Hopefully, know what it was like to be raised by the man Sam was proud to call his older brother. Even a father, at times, even a mother. Dean had always been there. He'd done everything Sam asked. Everything. Even when Sam told them not to contact him anymore and left for Stanford, Dean had done what he requested and left him alone, let him lead as normal a life as he could until he finally had to go get him.
Even soulless, Sam felt grateful. For everything Dean had done for him. For letting him be a kid as long as possible when they were younger. For stepping in and raising him when Dad couldn't, when Mom was never around. For all the hugs and comforting words and reassurances when Sam had a nightmare, when he got scared of the dark. For always staying at his side, no matter what, Dean had always, always stuck with him.
Sam let his gaze linger on Dean's face for a second more. His expression never changed, not once as he turned, heading down the sidewalk and brushing past Castiel as he did. As he walked farther from the house, he felt another stab of pain, but he didn't turn back.
Even soulless, Sam wanted Dean to have as normal a life as he possibly could.