The roots of son-preference lie deep in Chinese culture. Traditionally, the bloodline passes through the male side.
Women also "marry out", joining their husband's families and looking after their in-laws, not their own parents. For a long time, a son was your pension. Having a girl was wasteful. "Even though son-preference is not rational from the viewpoint of society as a whole, it is a rational choice for an individual," says Li.
Chen's home lies near lush rice paddies, where farmers in wide-brimmed straw hats bend double. The community used to rely on agriculture and believed a boy was necessary for the heaviest work in the fields.