Former soldier Do Duc Diu prays at the cemetery where twelve of his children are buried, after showing the graves to reporters, near his house in Quang Binh Province in central Vietnam April 11, 2015. Twelve of his fifteen children died from illnesses that the family and their doctors link to Do Duc Diu's exposure to Agent Orange. Do Duc Diu served as a North Vietnamese soldier in the early 70s in areas that were heavily contaminated by Agent Orange. He only found out about the possible dangers of Agent Orange before his last child was born in 1994. He said that if he had known about the possible effects of Agent Orange he would not have had children. Before he found out about the effects of Agent Orange, Do Duc Diu said that he and his wife visited many spiritual leaders and prayed at different shrines as they attributed their children's sickness to their ill-fated destiny. REUTERS/Damir Sagolj 

A former soldier Do Duc Diu is kissed by his disabled daughter Do Thi Nga as his wife sits at the doorway of their house in Quang Binh Province in central Vietnam April 11, 2015. Twelve of his fifteen children died from illnesses that the family and their doctors link to Do Duc Diu's exposure to Agent Orange. Do Duc Diu served as a North Vietnamese soldier in the early 70s, in areas that were heavily contaminated by Agent Orange. He only found out about the possible dangers of Agent Orange before his last child was born in 1994. He said that if he had known about the possible effects of Agent Orange he would not have had children. Before he found out about the effects of Agent Orange, Do Duc Diu said that he and his wife visited many spiritual leaders and prayed at different shrines as they attributed their children's sickness to their ill-fated destiny. REUTERS/Damir Sagolj 

Doan Tue holds his granddaughter, as a picture of him in military uniform hangs on the wall, at their family house in Truc Ly, in Vietnam's Quang Binh province April 11, 2015. Doan Tue, a soldier who served on 12.7 mm anti-aircraft guns during the Vietnam war, said he lived in several areas that were contaminated by Agent Orange. Two of his sons were born with serious health problems and the family and local health officials link their illnesses to their father's exposure to Agent Orange. His older son died two years ago. REUTERS/Damir Sagolj 

Phan Van Lam falls out of a hammock in his family home in Quang Binh Province in central Vietnam April 11, 2015. Phan Van Lam's father, a former fighter with the North Vietnamese army, said he was not directly sprayed with Agent Orange during the Vietnam war but lived in areas that were heavily affected by the defoliant. Local doctors told him that his son's health condition, which includes severe brain damage, is linked to Agent Orange. REUTERS/Damir Sagolj 

Dang Thi Quang and her son Nguyen Van Binh are reflected in an aquarium in their home in Vietnam's Quang Binh province April 11, 2015. Nguyen Van Binh’s father, a soldier who served in the North Vietnamese army's transportation unit, travelled and spent time in areas known as hotspots for Agent Orange contamination. REUTERS/Damir Sagolj 

Lai Van Manh rests in bed as his father Lai Van Bien receives guests in their house in Tuong An village, in Thai Binh province in northern Vietnam April 9, 2015. Lai Van Bien, a former intelligence officer in the North Vietnamese army, said that during the Vietnam war he served in an area that was heavily contaminated by Agent Orange. Lai Van Bien and his wife now care for their two physically and mentally disabled sons whose health condition the family and local officials link to the effects of Agent Orange. REUTERS/Damir Sagolj 

Lai Van Manh smiles as he lies under a mosquito net in the family home in Tuong An village, in Thai Binh province in northern Vietnam April 9, 2015. His father Lai Van Bien, a former intelligence officer in the North Vietnamese army, said that during the Vietnam war he served in an area that was heavily contaminated by Agent Orange. Lai Van Bien and his wife now care for their two physically and mentally disabled sons whose health condition the family and local officials link to the effects of Agent Orange. REUTERS/Damir Sagolj 

63-year-old former soldier, Nguyen Hong Phuc, sits on the bed with his son Nguyen Dinh Loc, 20, who is recovering from tumour surgery at Friendship village, a hospice for Agent Orange victims, outside Hanoi April 8, 2015. Nguyen Dinh Loc has serious mental and physical problems that his family and doctors link to his father's exposure to Agent Orange. His father joined the military after the U.S. army stopped using Agent Orange in 1971, but lived in areas heavily contaminated by it, including near Danang airport, where the chemical defoliant was stored. REUTERS/Damir Sagolj 

Nguyen Thi Van Long (R) and her best friend Dinh Thi Huong, who is deaf and mute, spend time together at Friendship village, a hospice for Agent Orange victims outside Hanoi April 8, 2015. The fathers of both girls were soldiers who were exposed to the Agent Orange during the Vietnam war and health officials link the girls' health conditions to the defoliant. Some 120 children and 60 Vietnamese veterans stay at Friendship village, which was established in 1998. REUTERS/Damir Sagolj 

Nguyen Thi Ngoc throws a ball to her friend and roommate Dang Thi Nu (R) in the exercise room at Friendship village, a hospice for Agent Orange victims outside Hanoi April 8, 2015. Dang Thi Nu's grandfather, a former soldier in the Vietnam war, was exposed to Agent Orange and health officials consider her mental and physical conditions to be linked to it. She has lived at Friendship village for almost ten years. Some 120 children and 60 Vietnamese veterans live at Friendship village, which was established in 1998. REUTERS/Damir Sagolj 

Nguyen Thi Thiet (L) and Nguyen Thi Phuoc, who suffer from mental and physical illnesses, rest in their wheelchairs in their brother's house in Danang April 12, 2015. According to an official from the local Association for Victims of Agent Orange/Dioxin, their father was exposed to the Agent Orange while serving as a driver for the South Vietnamese army and his children's health conditions are linked to it. REUTERS/Damir Sagolj 

Disabled children, who suffer from various mental and physical problems, wait for lunch at Peace Village in Tu Du hospital in Ho Chi Minh City April 14, 2015. According to the head of Peace Village, more than two-thirds of its over 60 patients are from areas that were heavily sprayed by Agent Orange, but some patients at the unit suffer from problems that are not related to Agent Orange contamination. REUTERS/Damir Sagolj 

Pham Thi Phuong Khanh is fed by a hospital staff member at the Peace Village in Tu Du hospital in Ho Chi Minh City April 14, 2015. Both of Pham Thi Phuong Khanh's parents were exposed to Agent Orange during the Vietnam War. According to the head of the Peace Village, more than two-thirds of its over 60 patients are from areas that were heavily sprayed by Agent Orange and their health conditions are linked to the use of the defoliant. REUTERS/Damir Sagolj 

12-year-old Tran Huynh Thuong Sinh is fed by a hospital staff member at the Peace Village in Tu Du hospital in Ho Chi Minh City April 14, 2015. Tran Huynh Thuong Sinh, whose parents and grandfather were all exposed to Agent Orange, was born without eyes and with other serious health conditions. Officials at the hospital link his health problems with exposure to the defoliant. According to the head of the Peace Village, more than two-thirds of its over 60 patients are from areas that were heavily sprayed by Agent Orange and their health conditions are linked to the use of the defoliant. REUTERS/Damir Sagolj 

Faded composite pictures of Dang Van Sanh (R) and his wife Nguyen Thi Thin hang on the wall of the family house in Le Son Bac village, north of Danang April 12, 2015. Dang Van Sanh was directly sprayed by Agent Orange while fighting in a jungle during the Vietnam war and later died of throat cancer. He had four children of which two died just after birth. His son Dang Van Son survived but is disabled, as is his granddaughter. Their family and health officials blame the defoliant for their health problems. REUTERS/Damir Sagolj 

38-year-old Doan Thi Hong Gam, who suffers from severe mental as well as physical health problems, covers herself with a blanket in an empty room in Thai Binh province, northern Vietnam April 10, 2015. Doan Thi Hong Gam spends her time in an empty room. She is kept isolated because of aggressive behaviour linked to mental health problems. Her father, who suffers from serious heath problems, served as a North Vietnamese soldier during the war and said he was exposed to Agent Orange while fighting in the central highlands. Doan Thi Hong Gam’s family and health workers believe her health problems are linked to Agent Orange. REUTERS/Damir Sagolj 

Pictures and diplomas belonging to Doan Ngoc Uyen and Le Thi Teo, both former soldiers, decorate the wall of their family house in Thai Binh province in northern Vietnam April 10, 2015. The couple's daughter Doan Thi Hong Gam suffers severe mental and physical health problems, which the family and health workers believe are linked to Agent Orange. Doan Thi Hong Gam's father, who now suffers from serious health problems, served as a North Vietnamese soldier during the war and was exposed to Agent Orange while fighting in the central highlands. REUTERS/Damir Sagolj 

16-year-old Le Dang Ngoc Hung, who suffers from mental and physical health problems, rests under a mosquito net in the family house in Phuoc Thai village, outside Danang April 12, 2015. Le Dang Ngoc Hung's grandfather Le Van Dan, a former artillery soldier with the South Vietnamese army, said he was exposed to Agent Orange more than once, including being directly sprayed by U.S. planes near his village before he joined the military. Health officials confirmed two of his grandsons’ disabilities are due to his exposure to the defoliant, Le Van Dan said. REUTERS/Damir Sagolj 

Le Van Dan (C) looks at his disabled grandson Le Van Tam (L) as his daughter feeds another sick grandson in their family house in Phuoc Thai village, outside Danang April 12, 2015. Le Van Dan, a former artillery soldier with the South Vietnamese army, said he was exposed to Agent Orange more than once, including being directly sprayed by U.S. planes near his village before he joined the military. Health officials confirmed two of his grandsons’ disabilities are due to his exposure to the defoliant, Le Van Dan said. REUTERS/Damir Sagolj 

7-year-old Nguyen Van Tuan Tu, who suffers from serious health problems, is looked after by a family member under a mosquito net in their house near the airport in Danang, in central Vietnam April 12, 2015. When Nguyen Van Tuan Tu's father started working at Danang International Airport in 1997, he was not aware of the health risks associated with Agent Orange and he collected fish and snails from a contaminated lake nearby for the family to eat. His first child to be born after he started working at the airport, was born in 2000 and died in 2007. Nguyen Van Tuan Tu was born in 2008 with same symptoms as his late sister and doctors and parents believe their health problems are linked to effects of Agent Orange. The couple have one healthy daughter who was born in 1995, before they started working at the airport, and she is now a university student. Danang airport was a U.S. airbase during Vietnam war and since 2012 both the U.S. and Vietnam are conducting a clean-up operation at the site. REUTERS/Damir Sagolj 

Dang Van Son, a physically disabled lottery ticket vendor, is reflected in a framed picture of his father Dang Van Sanh, a late former North Vietnamese soldier, at the family house in Le Son Bac village, north of Danang April 12, 2015. Dang Van Sanh was directly sprayed by the Agent Orange while fighting in a jungle during the Vietnam war and later died of throat cancer. He had four children of whom two died just after birth. His son Dang Van Son survived but is disabled as is his granddaughter. The family and officials blame the defoliant for their health condition. REUTERS/Damir Sagolj 

The cleaning operation of the area that was used for storing Agent Orange is seen from a plane taking off from Danang international airport April 13, 2015. Agent Orange was stored at Danang airbase and sprayed from U.S. warplanes to expose Northern Vietnamese troops and destroy their supplies, in jungles along the border with Laos. Since 2012, both the U.S. and Vietnam have been conducting a clean-up operation at the site. REUTERS/Damir Sagolj