Half siblings definitely looks like a good possibility--the cousins look like cousins, the aunt looks like an aunt, and the suspected half sibling looks like a half sibling--all of those people came up in the range you'd expect to see.
Network President Jenny LeFevre, Agent Orange Victims and Widows Support Network, attributes more than 250,000 deaths to Agent Orange, a toxic herbicide the U.S. military sprayed over Vietnam from 1962 to 1971.
In one of the first Search and Destroy missions northwest of Dau Tieng, named Operation Attleboro, a U.S. report states that 115 U.S. soldiers were killed, while the North Vietnamese lost 1,062. In Operation Junction City, the report also states that 282 U.S. soldiers were killed while the Viet Cong lost 1,728 guerrillas.