For as long as Sam could remember, Dean was the only person he could ever rely on. They moved around too often to make any friends, they only visited Uncle Bobby once in a blue moon, and their parents were always, always gone. John's absence Sam understood: "He's working", Dean would say. "He's got really important work to do." His lack of a father he could chalk up to business, but his mother? She was just…gone. Sam usually didn't think much of it - he was too young - but around the time he turned five, curiosity got the better of him.

It was just any other day when Sam finally decided to ask. He and Dean were sitting in the motel, waiting for John to get home wile watching reruns of old cartoons. Sam looked up at his older brother, figuring he was the only person that would answer him, and trusting him to give the truth. He popped the question in a soft voice with all the innocence of a toddler, "Dean, where did Mommy go?"

His big green eyes, all wide with wonder and anticipation, watched as Dean's face changed in a way he'd never scene before. It became stiff, his eyes a little distant and cold as he looked down at him. "What?" Dean asked, obvious restraint showing through his voice. Sam didn't understand this, so he pressed on.

"Mom, she's never here. Even less than Dad is. Where did she go?"

Dean inhaled sharply before responding, "She didn't go anywhere, Sam. She just..can't see us, right now."

"Does she have work too?"

"No, she doesn't. Now just watch the show," Dean ordered, turning his attention back to the TV with his jaw set.

"But Dean-" he began to plead, but Dean wasn't having any of it.

"Please, just stop asking, Sammy."

It was strange; Dean had never avoided a question Sam asked before, which only made him more curious. Not only for the truth, but to see what he'd do next.

"If she doesn't have work, why did she leave us?" Sam asked earnestly, pulling his entire body onto the couch to turn and face his brother. What came next was entirely unexpected, and caught him completely off guard.

"She didn't leave us, Sam!" Dean snapped, "She's dead, okay? She died, a long time ago, and we'll never see her again!" It happened so suddenly, the way he turned to him and shouted directly in Sam's face.

It scared him.

Sam scrambled backwards on the couch, curling up into a ball with wide eyes and tears running down his cheeks. It was the first time Dean ever yelled at him, and though he didn't quite understand the concept of "dead", he knew he must've done something wrong. When John got angry at them like that, it meant they were in trouble, and then came the swats. Sam was scared Dean was going to hit him too, and then go away just like their dad always did. Dean was the one person Sam knew would never leave him, but for the first time, he thought that he would.

He didn't want to end up alone.

Hands holding his head down in preparation for the expected beating, Sam tried his best to speak through his sobs and ended up stuttering over his words. "I-I'm s-sorry, Dean, I didn't, I'm sorry."

When Dean's hand finally did reach him, it was not to hit him but to pull the younger boy into a hug. "I'm so sorry, Sammy," he said softly, his voice the very definition of apologetic, "I didn't mean to yell like that. I'm sorry."

Sam still didn't understand, but he knew that Dean was there, so he reached out to wrap his arms around his brother's torso and wail into his shoulder. His hands held onto the back of Dean's shirt as tightly as they could, as though he'd disappear if he didn't.

Dean started rubbing his back to comfort him, "It's okay, Sammy, I'm right here. I'm not gonna leave you. We don't need anyone else; I'll take care of you. You know that, right?" Too busy crying to answer verbally, Sam just nodded his head against Dean's shoulder.

"Good. It's just you and me, Sammy, to the very end. Promise."