I'm sorry you and your family are experiencing such pain. We have experienced it twice in our family. We won't understand until we get home for the answer: 2 Cor 4:16-18

Therefore we do not lose heart. Though outwardly we are wasting away, yet inwardly we are being renewed day by day. For our light and momentary troubles are achieving for us an eternal glory that far outweighs them all. So we fix our eyes not on what is seen, but on what is unseen, since what is seen is temporary, but what is unseen is eternal.