They prayed. A lot. Dean remembers teaching 4 year old Sam the prayer they'd do before they went to bed. Dean remembers always making Sam pray before they ate. Dean remembers hearing Sam pray to their mom too. They'd also pray when John was late home. They always prayed.
Dean stopped praying at 12 when John came home, barely able to function. Sam kept praying. He prayed for Dean to do good in school and John go come home safe from hunts. They no longer prayed together. Not before meals or bed. Sam always prayed though.
At 14 Sam's prayers changed. They went from asking for good things to happen to his family to asking for forgiveness and change. His prayers changed one hot June afternoon when Dean was washing the impala and turned and winked at him. Now instead of Sams prayers being full of "let Dean pass math." and "please let dad be safe" turned into "don't let me look at him that way. Don't let me feel this way. Please forgive me I know it's wrong I can't help it. I don't want to love him like this. Don't let me be a freak." Dean never heard Sam's begs and cries at night while he laid in bed praying for forgiveness.
At 19 Sam finally stopped praying. It happened in September when Dean cut him off for good. Dean sent all Sam's calls to voicemail and ignored his texts. Sam didn't have anything to pray for anyway. Dean hated him. John hated him. He was alone, clinging to memories. Sam never prayed again simply because he never saw his angel again.
