Sam watched with an increasing sinking feeling as Lisa broke down before his eyes. He had been trying to be as careful and as gentle with this as possible but it had been inevitable that he'd say something that would trigger a cascade of memory, in this case, Ben.
Sam attempted a reassuring gesture by placing his hand on her back. "He couldn't tell you. It was too risky." He started to speak, to try to ease her suffering but was stopped in his tracks by what she said next. Ben's Father? He knew Dean had had his suspicions when he'd first met the kid but Lisa had told him he wasn't his. It was possible her memory was convoluted somehow with the rush of things coming to her now but if it was true and Dean had known it he had never told Sam.
The thought threw him so much he only barely realised in time that she was about to pass out, only just catching her before she hit the floor. Shit, If Dean was actually still in Marrowood then he was going to kill his little brother. Sam lifted Lisa and lay her gently on the couch, if he remembered this part right then there was very little he could do for her now, it was all down to her overloaded subconscious. He sighed heavily and sat down in a chair next to the couch, maybe he couldn't do anything to help her but he'd be damned if he was leaving her alone when she was like this, unless Dean came back.