So they weren't actually brothers. They were what humans called 'adopted'. It made far more sense to Castiel now. Four boys and a girl, all adopted by the same man. Sure, it was entirely acceptable. He wasn't aware how very rare it was, so he just accepted it for what it was, at face value.
It was the bit about the resurrection, though, that really gained his attention. Lazarus Pit? This man had died and come back. It explained a lot about the state of his soul, actually. It explained a little more than Castiel had really wanted to know. It suddenly all made a lot more sense, his blue eyes racing over Jason's face-- inspecting the heart of his soul.
"Your dog." He repeated the words because he hadn't been listening to what was said over the last minute, so much as how it was said. But it came to him after a few seconds of consideration, that dark head tipping curiously. "He tells me a lot." The words were so factual, as if he were telling Jason that yes, the sky was blue. Why was he asking?
Thankfully, they were both saved for the moment when the waitress returned with that burger, cheese and bacon on the side, and refilled Castiel's half-sipped-at cup coffee. She gave them both a smile, inquired after needing anything else, then headed on her way, leaving the two alone again.
"What do you remember of dying?" Whatever he'd gained from the dog would have to be left for later, those intense blue eyes were now locked, stationary, onto green. He didn't blink. He didn't look away. He didn't waver. There was something curious about the whole thing and the angel found that he wanted to know. More than wanted, maybe. Perhaps he needed to know.