Hallie Fuchs struggled with rashes, brain fog and sinus infections so severe she needed surgery until TikTokers saw the black marks on her vent in the background of a video, and realized it was mold.

Photographs by Gabriel V. Cárdenas for CNN Edinburg, Texas (CNN) — Patriotism runs deep in this South Texas town nestled just along the border with Mexico. American flags fly outside many businesses.