Trump: Mexico will pay U.S. back for the 'Great Wall'
This could cost taxpayers as much as $25 billion.
Life in Trump's America: A deportee explains how walls destroy families
She was brought into the U.S. as a child—and now she may never return.
Can Donald Trump really build a border wall to Mexico?
Trump's wall faces a slew of hurdles before it can become a reality.
31 dead, 72 injured after fireworks market explodes in Mexico
The cause is still under investigation.