Obon in Japan, Ullambana in China, Pchum Ben in Cambodia: the seventh lunar month opens the gates and the dead come home for a visit. The origin story is Moggallana finding his mother reborn as a hungry ghost, unable to eat, and being told by the Buddha that only the collective merit of the sangha could reach her — which is how a religion of individual liberation acquired an ancestor festival. Families sweep graves, lay out food, burn paper money and goods, and float lanterns downriver at the close to see the dead off. In practice it is the point where Buddhism and Chinese family religion became a single thing.