Dean's question should be easy to answer, but Castiel soon realizes that he.. does not know what to say, and it shows. He inhales softly, a quizzical expression flitting over his face, something dark ghosting behind his eyes before he averts them, looking down and away.

"I.. I don't know."

It's the best answer that he can give. His father might have been grateful to Castiel for finding him here, but he has never been a particularly warm man, never shown Castiel much love. He's been a decent enough father, and he is good at what he does, but there has been little enough gentleness in his upbringing, and the man who raised him feels more a stranger than kin more often than not.

"I'm not important. I'm not sure he would waste the resources to find me."