The family should live in such a way that its members learn to care and take responsibility for the young, the old, the sick, the handicapped, and the poor. There are many families who are at times incapable of providing this help. It devolves then on other persons, other families, and, in a subsidiary way, society to provide for their needs: "Religion that is pure and undefiled before God and the Father is this: to visit orphans and widows in their affliction and to keep oneself unstained from the world."
Source: Catechism of the Catholic Church (Vatican.va)