Given the difficulty in defining family, it
may be useful to conceptualize the characteristics and functions
of family units. First, many families share biology, including temperament, personality,
talent, and disease vulnerability. Second, families typically have
a power hierarchy that is determined in part by age, generation,
culture, personality characteristics, and gender. Third, families
tend to have their own “culture,” which includes
a family-specific set of values, goals, and expectations. Although they
are unique to each family, these “microcultures” reflect
the larger societal and ethnic cultures. Fourth, every family has
an “invisible boundary” that defines who is a
member and who is not.