Quote from Bill in Pilot
Bill: Shh. Be cool. Adult Dean: "Be cool" was Daddy's catch-all advice for every situation. [flashback to Bill throwing a match on the grill:] Bill: Be cool. [flashback to Dean gasping as he's electrocuted by a wall socket:] Bill: Be cool. [flashback to Bill in the driver's seat with his family as their car is stopped by the police:] Bill: Be cool.