The short version is: I don't know.

The prophet Joseph Smith said:
"While one portion of the human race is judging and condemning the other without mercy, the Great Parent of the universe looks upon the whole of the human family with a fatherly care and paternal regard; He views them as His offspring, and without any of the contracted feelings that influence the children of men, causes 'His sun to rise on the evil and the good, and sendeth rain upon the just and the unjust.' He holds the reins of judgment in His hands; He is a wise Lawgiver, and will judge all men, not according to the narrow, contracted notions of men, but, 'according to the deeds done in the body whether they be good or evil,' or whether these deeds were done in England, America, Spain, Turkey, or India. He will judge them, 'not according to what they have not, but according to what they have', those who have lived without law, will be judged without law, and those who have a law, will be judged by that law."

In other words, everyone will be judged based on their particular life, and not on anyone else's. God will say, "This is what I gave you, and this is what you could have done with that," and you will know that you deserve whatever fate you get. So will everyone else, eventually. But in this life, what makes you think that you, me, or anyone else should or can know everything about a person, so we can judge them.