Nothing But A Ghost Story

"It's for the Greater Good," Gellert told him. "The Greater Good of whom?" Albus countered. In the end, it doesn't matter because they're both different sides of the same coin - and the only thing important is the metal they're imprinted on. Or a story about Albus's, Gellert's, Aberforth's and Ariana's relationship over the years. Canon-based, but basically AU.