Things will get interesting when this guy croaks.
http://www.businessinsider.com/simon-henderson-succession-could-place-saudi-arabia-in-crisis-2014-12
Theoretically, his successor would be his half brother Crown Prince Salman, who is seventy-eight. Despite the appearance of robustness given by a heavy public schedule of meetings, Salman’s brain is evidently ravaged by dementia. Visitors report that after a few minutes of conversation, he becomes incoherent. The fact that Salman appears in public at all is attributed to his determination to become king — or, more likely, the ambition of his closest relatives that he should do so.
Such are the rivalries in the House of Saud that King Abdullah has been unable to displace Salman, although last March he appointed another half brother, Muqrin — the youngest surviving son of Saudi Arabia’s founder, King Abdulaziz, also known as Ibn Saud — to the new position of deputy crown prince.
Controversially, this meant passing over the claims of other half brothers and maneuvering in the Allegiance Council to secure an advance baya, or oath of allegiance, to try to cement Muqrin’s new status. Significantly, Muqrin’s confirmation was officially reported as not unanimous.