It wasn't seeing the big brother holding his little brother by the hand as they walked out of the corner store behind their mother that did it. It wasn't the impossibly tall teenager with shaggy hair and torn jeans walking past Dean that did it. It wasn't Sam's Stanford Student ID that he kept tucked into his wallet that did it.
What ripped Dean's heart out was the little old lady in line in front of him at the register of the corner store, talking to the almost-as-old clerk.
"I'm so sorry about your daughter." The clerk said. "It happened so fast, didn't it?"
"Only a week." Little old lady agreed. "Her eyes were bothering her and she went to eye doctor. He sent her for a cat scan and they found the brain tumor. They operated the next day but she -." She stopped herself there, but Dean could figure what happened. "One day she was fine, five days later she was gone."
She wiped her eyes and the clerk made the appropriate sounds of comfort.
"She was my baby." The lady went on. "I know she was fifty three and expecting her own first grandbaby already but since I lost her - my arms just feel empty."
That did it. That ripped Dean's heart right out of his chest. He turned and shoved his purchases on the first shelf he came to and hurried out to the car. He got inside, slammed the door, and gripped the wheel tight in his hands.
Since Sam - ever since - since - ever since then, Dean had felt everything in the book and then some. Anger, despair, depression, rage, but he'd never had a name to put to the dull ache of loss and regret that traveled with him every second of every step of every minute of every day.
His arms felt empty.
From the very first time Mom had laid Sam in his arms, that first day at the hospital, there'd been a weight in Dean's arms. Not an oppressive weight, not a chore, not a burden. Holding Sam, carrying him, bearing that weight had always been a privilege. Then after the fire, after losing Mom, it became a comfort to Dean. Day after day and night after night, those first few months - maybe even that whole first year - Dean would hold Sam even when he didn't have to, sleep curled around him at night, just to have that weight in his arms.
All their lives, picking Sam up, teaching him to walk, helping him take his baths, putting him to bed, and then later when he started hunting, picking him up hurt, helping walk back to the car, tending his wounds, putting him to bed - that weight reminded Dean he wasn't alone, that somebody needed him and depended on him. Loved him.
His arms felt empty.
He barely made it back to Lisa's, hurrying through traffic, needing to get someplace alone and quiet. The house was empty. He shut the door and leaned back against it, letting the sobs finally overtake him.
He had a beautiful woman who loved him, a smart and strong boy who looked up to him, three home cooked meals every day, the same bed every night, pie whenever he wanted it - and a hole in his gut bigger than the one that had taken Sammy away from him.
His arms felt empty.
The End