Hassan Ali / Reuters Saudi Arabia's Crown Prince Nayef bin Abdulaziz al-Saud speaks at a news conference about haj preparations in Mecca in this November 1, 2011 file photo.

As Saudi Arabia mourns the death of Crown Prince Nayef bin Abdul Aziz Al Saud, heir to the throne, there are likely to be as many gasps of apprehension as secret sighs of relief.

It’s still not clear where Nayef, 78, was at the time of his death. Late last month he left Saudi for routine medical tests and a holiday at an unknown destination. Government officials, who said he was in good health as recently as June 3, had expected him back in the country “soon.” The death of Nayef, who was also deputy Prime Minister and Minister of the Interior, comes just eight months after the death of his brother and former Crown Prince Sultan bin Abdul Aziz, who was 86.

Nayef’s appointment as crown prince last year was controversial in some circles, particularly among a younger generation of would-be leaders who perceived him to be more socially conservative and less reform minded than his brother the king. There were fears that if he were to take the throne he might overturn some of the King’s reforms, such as the promise that women would be able to vote, and run, for the first time in 2015’s local council elections.

(OBITUARY: Crown Prince Nayef Has Died)

But the death of a second heir to the throne in less than eight months threatens to upset the kingdom’s fragile stability. King Abdullah bin Abdulaziz, who, at 87, has outlasted two heirs, will have some difficult decisions to make in the coming days as he presides over the appointment of the next crown prince. King Abdullah’s third brother, former governor of Riyadh and current defense minister Prince Salman, 75 is a likely choice, though the king’s half brother and Foreign Intelligence Chief Prince Muqrim, at a relatively sprightly 68, is also a contender.

With most of those directly in line to the throne hobbling about with canes, hip replacements or in wheel chairs, one could be forgiven for thinking of Saudi palaces as particularly well-appointed old age homes. The next few decades in Saudi Arabia are likely to be marked by a succession of funerals and coronations as the top position in the world’s largest oil exporter cycles through a generation that had more to do with the Kingdom’s foundations than it does with the country’s future. As the crown passes from head to head, it is likely to slow the process of reform and progress in a kingdom that in many ways still feels mired in the last century. The ruling family’s authoritarian grip on power may provide stability in the short term, but with half the population under the age of 18, and with a leadership almost entirely above the age of 70, it seems inevitable that tensions will rise.

(MORE: Why the Saudi Succession Spells Instability in the Long Term)

As I wrote in October last year, there is some speculation that the popular Mecca Governor Prince Khalid bin Faisal could also be in the running.

At 71 he may hit the mid range of the succession age spectrum, but his position of grandson to modern Saudi Arabia’s founding monarch, Abdul-Aziz, as opposed to son, would represent a revolutionary change that would have repercussions not only in the uppermost ranks of the country’s leadership, but could also open doors to a much younger and progressive generation in key ministries. As for the younger generation of Saudi rulers? There is certainly talent to be mined. But with more than 22,000 descendants of the founding royal family clamoring for position and recognition, it is unlikely that the succession will be smooth. As long as the sons of Abdul-Aziz are in power, the transitions will go in relatively orderly fashion, says says Gregory Gause, International Relations professor at the University of Vermont and a specialist in the opaque world of Saudi government. “But at some point it will have to go to the next generation. Some lines of the family will be privileged, and others will be sidelined. That will be tricky.” It opens up the possibility of splits in the family, political mobilization and mass politics – in short the very kind of instability that King Abdullah is currently trying to prevent. It may take a generation or two, but the Arab spring could yet bloom in the Saudi desert.

Aryn Baker is TIME’s Middle East Bureau Chief, based in Beirut. Find her on Twitter at @arynebaker. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIMEWorld.