The law of free will operates to determine a number of probable realities to generate certain experiences within an individuals life. These free will choices do have certain limitations, for if you become completely off track from a special destiny, life termination could occur. You also always have free will to mitigate the impact of an event or situation, even to transcend it entirely.
In general, young souls have the most free will, but little control over it. Older souls have less free will but more exercise over it.