Dean held Cas close. "Shhh. It's ok. You're fine. Calm down." He was desperately trying to calm down the distresses angel.
Cas, still shaken up from the dream, couldn't form the proper words to respond with. Instead, he just shook his head, and continued to sob.
"Do you wanna talk about it?" he asked, figuring if he knew what the dream was, he could begin to comfort him.
Again, Cas shook his head. "Too painful… too real…." He muttered, still slightly lost in his nightmare.
Dean nodded. "Well, that's progress. At least you can talk now." When Cas glared at him, he hastily added. "Sorry. But I'm sure it wasn't /that/ real."
"But it was! I /saw/ you!" Cas flinched, knowing that would intrigue Dean. He braced himself for an onslaught of unwanted, well-meaning but unwanted, questions.
"What?!" Dean raised an eyebrow. "Actually, never mind. You can tell me later" He ran a comforting hand through his angel's hair.
Cas nodded gratefully. "Thanks… for everything."
Dean smiled, and placed a soft kiss on Cas' forehead. "Ok. You want to go to sleep, now?"
"Mmhmm." He muttered, already half asleep. "Will you stay with me?"
"Of course."
"Night."
"Night."