Pham Thanh Cong leans forward, his 55-year-old face a patchwork of scars and dents, and explains what's wrong with My Khe hamlet. Vietnamese families are built around a three-generation structure, Cong says. Parents work the fields while grandparents take care of children. In time, children will become caregivers and grandparents the cared-for. Eventually, the generations will shift and the cycle will repeat. Families have been this way since there were families in Vietnam.