WASHINGTON (AP) — Melania Trump lit up when a 3-year-old boy darted out of "Family Unit 8" at a migrant center in Tucson, Arizona.

"Hello!" said the first lady, brightening amid the semicircle of eight cells in a short-term holding center for migrants. "How are you?"

Mrs. Trump, an immigrant and a mother herself, wanted to find out more about how her husband's strict immigration policy was playing out on the ground, especially among families that have been separated at the border. Two tours of migrant detention centers in a week gave her a sometimes grim view.

Now the question is what she does...