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.
U.S. Army Huey helicopter spraying Agent Orange over Vietnamese agricultural land. Agent Orange is the combination of the code names for Herbicide Orange (HO) and Agent LNX, one of the herbicides and defoliants used by the U.S. military as part of its chemical warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1972.