Canada

Under the nuclear family approach, children over 18 living with their parents are considered separate families and can qualify independently, regardless of their parents’ income. This raises equity concerns because it may result in disproportionate benefits for high-income families.

In contrast, the economic family definition uses the combined income of all related individuals living in the same household, providing a more comprehensive and equitable basis for assessing eligibility.

So, if my daughter lives in my house, we're all related, and thus one economic family.

But, if my daughter moves into my neighbor's house, and their son moves into my house, we're now four economic families?

How about once a month, we just direct deposit the same amount into the bank account of each and every person over the age of 18?

Simplicity makes it more difficult for paper-pushers to game the system to help the rich. So any suggestion to complicate it oughta be taken skeptically.