A couple tables are worth a thousand words. First, a few definitions from the Census Bureau:

A household consists of all the people who occupy a housing unit.

A householder refers to the person (or one of the people) in whose name the housing unit is owned or rented, if there is no such person, any adult member, excluding roomers, boarders, or paid employees.

A family is a group of two people or more (one of whom is the householder) related by birth, marriage, or adoption and residing together

Here are the tables, with minimal commentary:

_2018 Income Distribution by Age of Householder.png

So over half of young adults and seniors live in lower income households (bottom two income quintiles). What else?

_2018 Characteristics Associated with Income.png

A lot to ponder.