Functionalism - Parsons' 'Functional Fit' Theory (1):
> the functions that the family needs to perform will affect its shape or structure
> before the industrial revolution, the dominant family was extended - extended kin performed functions (childcare, healthcare and education) that were not provided by the state, and most families worked in agriculture so required many family members to work on and run the farm
> after the industrial revolution, the nuclear family become dominant, because it is geographically and socially mobile