As far as I know, under a unique definition of refugee that applies only to the Palestinians (as established by the UN Relief Works Agency), any descendant of a MALE (they exclude females who marry non-refugees) refugee is considered by international law a refugee, and is entitled to all the "benefits" associated with this label.The fact-checking reader also links to this book, which discusses the hypocrisy of the UNRWA, the group that instituted the obscure definition in the first place.
This article available online at:
http://www.theatlantic.com/international/archive/2009/09/on-the-definition-of-a-palestinian-refugee/27028/
