Head of Household
What we know: The census only explicitly tells you how a person was related to the head of the household. It does not necessarily reveal how anybody else was related. You might be able to reasonably guess at those other relationships from the census alone. However, in many cases you would want additional evidence.
Robert L. Stone (right) next to his father, Jake Stone (left), during a medal ceremony where Robert was awarded the Distinguished Flying Cross, September 5, 1945. (Gilder Lehrman Institute, GLC09620.342.01)