That's so sad, I lost my best friend at 16 years old, now I'm 52 and still think about her alot. There's just so many questions left unanswered, it can cause depression so i would keep an eye out if you start seeing signs of it in your child, just be strong for your children too as we as parents go through the grief too. Be a good example and teach them the courage they need too. I'll pray for everyone involved!