As far as the mentally challenged - we believe kids are accountable at the age of 8.... In the case of the mentally handicapped (retarded below that level) or those who die before that point, they go straight to the celestial kingdom. They are, in actuality, choice spirits who have not had to be tested in this life. In the case of those who had diminished capacities due to toxins, choices, etc., or even trauma, I believe they will have all things taken into accountability concerning the judgment.