I know how hard it is to lose a child. My brother lost His in Afghanistan. He was deployed for only two weeks before he was killed. It was a difficult time for all of us as we are a close family. He left a wife that was 8 months pregnant and his son will never know him till heaven. It takes prayer and don't get angry and blame God. I know that's the first thing we want to do. But God knows best. Instead, praise him and worship Him and He will bring peace like a river. The man that wrote "it is well with my soul" an old church hymn lost his whole family at sea and what a wonderful God praising song he wrote.
I know it's hard, but keep praising Him.