Siblings in the Supernatural universe.
From the Winchesters willing to sell their eternal souls for each other, to the witches who worked together for 600 years to raise Samhain; from the angels fighting shoulder to shoulder for untold centuries, to Ansem killing everyone who split he and his twin brother up. There are many reoccurring themes in Supernatural, but none as loud or as clear as this - that beyond the ghosts and demons and angels and monsters, this is a story about family. That the bond one shares with their brother/sister, be it through blood or not, or be it positive or not, it’s a force to be reckoned with. They chose family. And, well, isn’t that kinda the whole point?