Often a child is like an uncle or an aunt of the father or mother; why is this? It has two aspects: it may be either that the father or mother has the qualities of this relation, although in them they have not fully developed, and those qualities develop in the child; or it may be that the grandmother or grandfather or other relation is so much attached to his descendants that his spirit watches and impresses with his qualities the child that is born in that family. Heredity is a matter of vibrations. There must be harmony in the number of vibrations, in the same way that color and sound are made by the harmony of vibrations. Thus a person may be more like his grandfather than his father. If the grandfather has been a poet, the grandson may again be a poet if the number of the vibrations corresponds, even when the son is not one.