Supernatural, Season 4

Adam:
How can I help?

Dean:
You can't.

Adam:
This thing killed my mom. If you're hunting it, I want in.

Dean:
No.

Sam:
Dean, look maybe...

Dean:
(interrupting) Maybe what?

Sam:
He lost his mother. Maybe we can understand what that feels like.

Dean:
Why do you think dad never told us about this kid, Sam, huh? Why do you think he ripped out the pages?

Sam:
Because...

Dean:
(interrupting) Because he was protecting him!

Sam:
Dad's dead, Dean.

Dean:
It doesn't matter! He didn't want Adam to have our lives, okay? And we're gonna respect his wishes.

Adam:
Do I get a say in this?

Dean and Sam (in unison):
No!