Support WBURAt The U.S.-Mexico Border, Volunteer Medics Step In To Care For MigrantsPlay04:07Download AudioMallory FalkApril 23, 2019 ShareSergio, a Guatemalan migrant, recently visited a mobile medical van with his 2-year-old son, Dylan. Sergio thinks his son became sick in a holding facility, where they spent two days. (KRWG)