Found this over at TF.N
Interesting......Dunno what it is, but it was under a spoiler warning!!!!
The moment Darth Vader wakes up from his slumber, and Anakin Skywalker truly is no more, the force will cease to exist in the land of the living. No more force sensitive children will be born... And all that will remain are those that had the gift before the dark times came, and managed to survive the first waves of the purge.
The last two force sensitive beings to come to existance, will be Luke and Leia, born mere seconds before their father's death... And the only survivors of the actual Jedi purge, that will go on for a great many years after the events of ROTS, are, as we all know, Yoda and Obi-Wan Kenobi.
The four of them survive, not to save the galaxy, but to save the man that will.
mmmmm