THEN

Dean carrying his baby brother out of a burning house. Dean and Sam left alone again in some nameless motel room while Dad was gone on another hunting trip. Dean standing watch over Sam with a shotgun and a silver knife while he sleeps. Dean answering Sam's incessant nonstop questions even when he's tired of hearing them.

Dean forging Dad's name on Sam's report cards secretly proud of his brother's high grades. Dean giving Sam the last piece of pie. Dean as a teenager bandaging Sam's injuries from a training hunt. Dean annoying Sam with his latest Big Brother prank. Dean stepping in between Sam and Dad in another of their endless arguments. Dean watching with love and fierce pride as Sam graduates his high school class as valedictorian.