Growing up with two married parents may be the greatest privilege of all, according to an influential US economist.

Melissa S. Kearney came to this conclusion after more than two decades worth of research on poverty and social inequality. She says there is widespread resistance to this idea within academia both for personal and ideological reasons.

Her upcoming book, the Two-Parent Privilege, published by the University of Chicago Press, she says in nearly all advanced economies, the share of people getting married has plummeted in recent decades.

Such trends are problematic, Kearney says, because of the lost economic benefits.

The reason marriage is so powerful is because two people combining their income, assets and time create economies of scale that can support families on a range of fronts, whether it be securing a mortgage or paying for childcare.

Research from the Marriage Foundation, a thinktank, previously found that nearly 90pc of new mums across Britain’s richest households were married.

This then dropped to just over 20pc when looking at the UK’s poorest.

Notably, children whose parents are married also tend to earn more than their peers.