The death of children and God's mercy brings inflation of comfort and humility. It speaks about something that is often painful for many, that you might even question about.
So why does God allow children to die?
This explanation reminds us all that. Why death is part of the existence of human? The judgment also follows for everyone. So what leads to that is the idea that children, in their innocence, are not to be held that accountable, the way adults are willing to be accountable.
When a child dies, heaven is open to their retarded judgment. That brings a peace of, that brings us peace to a topic that is usually impossible. So we explain how God's decision will stay the mercy, even when the same has, from that same point of view, the judgment of God.
The example of Noah's time and Sodom and Gomorrah shows how God may move those innocent children from an environment that could eventually corrupt or expose them to more greater evil. Whether we agree or not, but this message is calling us to trust God's wisdom beyond our limited understanding.
So it's a comforting reminder that God's mercy extends even in the moments where we fear the most.