And how the seemingly endless wait in the US is affecting their development.

This episode was produced by Victoria Chamberlin, edited by Sean Rameswaram and Matt Collette, fact-checked by Laura Bullard and Victoria Dominguez, engineered by Paul Mounsey, and hosted by Noel King.

Here's a link if you want to contribute to Today, Explained to Kids: bit.ly/texkids

Transcript at vox.com/todayexplained  

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