Almost all modern political systems share at least one guiding principle: that the people within them should be born free and equal. Ensuring that  equality — a fair start for all people — is required to legitimize those systems.

So, how are our political systems doing these days, in terms of their legitimacy?

Not very well. Oxfam drew much attention last week with a report calculating that the 62 richest billionaires in the world own as much wealth as the poorer half of the world’s population. If we extrapolate that report to children and consider the vastly different opportunities children have in life, with some children mining the cobalt for other children’s smartphones, its unclear where the fair start that legitimizes our political systems actually exists.

What’s the solution? Oxfam was right to call for more aggressive tax enforcement and investment in public services. But they missed perhaps the most compelling rationale for that enforcement and plan for that investment: Giving every child a fair start in life. The Having Kids model can help.