Prince George is born.
So the constitutional monarchy is stable for four generations.
When they asked us in 1999 whether we wanted to remain a constitutional monarchy or a republic, all except one small territory chose the monarch.
The republicans keep telling us that a republic is inevitable, but it has been inevitable for such a long time, it seems it will always be inevitable.
And this is as it should be, for the very purpose, the raison d'être, of liberal democracy is the limitation of power. And the monarch limits the power of politicians.
Politicians intuitively want to maximise power and liberal democracy counter-intuitively limits power. So liberal democracy lives in creative tension between the desires of politicians and our decision to limit power in the name of common decency.