One of the challenges I face when sharing the lord with others and quite frankly for myself as well is the suffering of children. We all have experienced instances where defenseless children for what ever reason through sickness or tragedy have lost their lives. I know that these things will seem small in comparison to the next life but that doesn’t explain why a merciful God would need this suffering from someone not old enough to know what sin is.
There’s a critical flaw in your thinking. The suffering of little children is not something God either needs or wants. He didn’t create the world this way. It became this way when sin was introduced into the creation. Since then the whole world has been under the control of the evil one (1 John 5:19) who Paul has called the god of this age (2 Cor. 4:3-4). He’s the responsible party.
God is even more upset than you are about this and sent His son to die so the effects of sin could be reversed. In the mean time, children who die go directly into the arms of the Lord where they’ll live forever as His children, rescued from all the sorrows and disappointments that accompany this life. I guarantee you not a single one of them would choose to return. They consider themselves to have been blessed.
You have a right to be upset about these things but you should direct your feelings toward the one who introduced sin into the world, not the One who gave His life so the effects of it could be reversed.