Erin Olivera waited weeks for doctors to tell her why her youngest son was paralyzed. Ten-month-old Lucian had started crawling oddly — his left leg dragging behind his right — and soon was unable to lift his head, following Erin only with his eyes.

She took him to a hospital in Los Angeles, but doctors there didn’t know how to treat what they saw. Lucian’s legs felt soft as jelly and he couldn’t move them. His breathing became rapid. The left side of his smile drooped as his muscles weakened. FULL REPORT