Final answer:
Middle-aged couples who care for both their children and aging parents are known as the sandwich generation. This term highlights their dual caregiver roles in the changing landscape of the family life cycle and generational responsibilities.
Step-by-step explanation:
Couples in their middle age who must fulfill the needs of both their children and their aging parents are commonly referred to as the sandwich generation. These individuals are "sandwiched" between the responsibilities of caring for their growing or grown children and their elderly parents. This phenomenon has become increasingly relevant as societal norms shift and the family life cycle changes due to economic factors, such as the Millennials who postpone traditional markers of adulthood due to economic constraints, leading to the Boomerang Generation.