Parents' work has shifted markedly around the world - and that goes for every region. Men in particular have been moving away from farmed-based work, and into industrial and post-industrial work - so they've moved away from the home. Women, likewise, have moved into the paid labor force and away from the home.

An essential criterion for any humane immigration policy is that it should allow families to remain together. Whether that means letting the entire family migrate together, or allowing a caregiver to travel back and forth across the border, it should make it easier for workers to be with their families instead of harder.

Parents' work has shifted markedly around the world - and that goes for every region. Men in particular have been moving away from farmed-based work, and into industrial and post-industrial work - so they've moved away from the home. Women, likewise, have moved into the paid labor force and away from the home.

Beginning in the 1800s with the Industrial Revolution, when women started to go into the formal workforce, leaving working at home to working in factories, countries realized they needed to do something. And they started to pass paid maternity leave.