With a combination of Census and survey data, Pew Research Center examined the experiences of multigenerational households, including who lives in these types of arrangements and why they do so.

According to the report resulting from that analysis, census data from 1971-2021 shows the number of people living in multigenerational family households quadrupled over that time, reaching 59.7 million in March 2021. The share more than doubled as well, to 18% of the U.S. population.

When asked why they share their home with relatives, Americans often give practical
reasons related to finances or family caregiving. The report from Pew Research Center continues that the experience also has an emotional component with about a
quarter of adults in multigenerational homes saying it is stressful all or most of the
time, and more than twice that share say it is mostly or always rewarding.

Other key findings include:

• A third of U.S. adults in multigenerational households say caregiving is a major
  reason for their living arrangement, including 25% who cite adult caregiving and
  12% who cite child care.
• A quarter of adults in multigenerational households say caregiving actually is
  occurring in their homes, either in the form of personal care for another adult in the
  household or care for a child younger than 18 who is not the caregiver’s own child.
• Upper-income adults are less likely than those with lower or middle incomes to cite
  caregiving as a reason for living in a multigenerational household

For more information, see the full report from Pew Research Center here.