I absolutely hate the sound of people who grind teeth in their sleep. The sounds of it make my jaw weak and all my teeth felt like they are melting away. But unfortunately, one of my son grind teeth in his sleep.
When I asked my child's doctor about it, he explains that a lot of children get this grind teeth problem due to their active lifestyle. They have so much things to do during the day and when they go to sleep, they need to wind down and de-stress. That's why they grind teeth as part of that process.
He told me the grind teeth problems will go away and true enough it is gone. If you want to learn more about grind teeth problems, read my parenting blog.