U.S. war veteran Larry Vetter conducts physical therapy exercises with 18-year-old La Thanh Nghia, near Da Nang, Vietnam. Nghia and his brother Toan, 21, are third generation victims of dioxin exposure, the result of the U.S. military's use of Agent Orange and other herbicides during the Vietnam War more than 40 years ago. The brothers were born healthy, but began to suffer from muscular dystrophy and other problems as they grew older. They are now confined at home as their bodies and lives waste away. Vetter, who served as a Marine Corps infantry officer near Da Nang during the war, met the family during his first trip back to Vietnam in 2008 and returned last year to finish a documentary film about Agent Orange. "They are part of my life now," he says. "And I'm part of theirs." The Vietnam Red Cross estimates that 3 million Vietnamese suffer from illnesses related to dioxin exposure, including at least 150,000 people born with severe birth defects since the end of the war. The U.S. government is paying to clean up dioxin-contaminated soil at the Da Nang airport, which served as a major U.S. base during the conflict. But the U.S. government still denies that dioxin is to blame for widespread health problems in Vietnam and has never provided any money specifically to help the country's Agent Orange victims. Jan. 5, 2013.