The doctrine of salvation for little children is not as complicated. They will have eternal life. They will receive a celestial glory. Any other doctrine is mockery before God (Moroni 8:23). Little children cannot repent; wherefore it is awful wickedness to deny the pure mercies of God unto them, for they are all alive in him because of his mercy (Moroni 8:19). Joseph Smith also recorded, I also beheld that all children who die before they arrive at the years of accountability are saved in the celestial kingdom of heaven (DC 137:10).