Did you know that Great Britain has so many Islamic children with mental
retardation that their socialist medical system is being crushed under it? It’s true. (You won’t hear about it much) It is the direct result of generations of “cousin” marriages. (Both bride and groom) First cousin marriage doubles risk of birth defects in children. It’s what can happen when 33% of the Pakistanis and other middle eastern migrants continue to inbreed. Disgusting tradition.
Back in Pakistan the motivator is keeping land and other property in one family. In GB, I can’t imagine why the custom would be maintained.