There are some traditions you inherit without anyone ever sitting you down to explain them. You simply grow up knowing. You know not to leave your chopsticks standing upright in a bowl of rice. You know why your grandmother might tell you not to whistle at night. You know why certain offerings are left outside rather than brought into the house. And then there is the seventh lunar month. 鬼月  Gwái Yuht. Ghost Month. For many Chinese families, especially those who grew up with Cantonese parents and grandparents, the seventh month carried a different kind of atmosphere. The streets felt different. The incense seemed heavier. Paper offerings appeared outside. Tables were covered with fruit, rice, tea and other foods. And somewhere in the background was the warning:  “Be careful. The ghosts are out.”  As children, we heard the warnings. As adults, we begin asking a different question:  Where did all of this come from?  Because the Hungry Ghost Festival isn't simply a...