I just learned about this
from a couple weeks ago suggesting lower payroll taxes for parents who
sacrifice to have the children who will someday pay for everyone on
Social Security, including those without children. If that’s too
confusing RTWT.

 By raising and educating their children, parents provide the
system with essential human capital. The cost of this contribution, in
both direct expenses and forgone wages, is often measured in the

 Yet parents get no compensation from Social Security, nor from
the wider economy, for the investments they make in their children.
Instead, Social Security pays the same benefits, and often more, to
people who avoid the burdens of parenthood. So long as Social Security
effectively penalizes people for having the very children the system
requires, it contributes to a downward spiral of falling birthrates
leading to higher and higher tax rates.