What is a dream?
It is a sample of a realm which is not defined/limited by time and space.
For a possible existence in that realm, one has to leave the time/space realm first (as in deep sleep).
Everyone was born to exist in this life not by his own will. Also, one's existence in a dream starts then ends at wake-up beyond his will as well.
Speaking logic, the outsider Will that let us exist in those two realms without getting our permission has also the choice to let us exist (or not) in a dream-like realm even after death. Obviously, one's existence in this possible dream-like realm, not defined/limited by time/space, won't end by a wake-up anymore