Sorry to hear that Scotty! But, it could always be worse and he will heal and be riding again before you know it! These things happen, just important to wear the correct safety gear to minimize damage!
Side story if I may...A conversation from an acquaintance this past week...their son was over at a friends house for a sleep over, just playing video games, watched movies and just being teenagers. They went to bed at a reasonable time and when the friend went to wake up their son, he didn't wake up. No drugs or alcohol involved and no health issues were known to be present. It's going to take 4 weeks for the autopsy results and the family is completely distraught as you can imagine. So, it can always be worse...but that's not news to anybody, just sad that it happens.
So, just live each day as if it would be your last and always tell your family you love them! Hang in there Scotty and be there for your son, all will work out!