Jeremy, glad your son is going to be OK and it drives the point home that kids belong in the back seat, Heck, my daughter even makes her lab sit in the back seat with her seat belt on (yes, they make doggy seat belts) when traveling.
Another thing some folks should think about if you have one of those small pickups (Ranger size) with the extended cab is those sideways rear seats. A good friend of mine in the Tampa area, another teacher and woodcarver, had his 7-year old securely bucked in the back during a minor accident. The accident was a low speed head-on in the mall parking lot, so slow the air bags did not even go off. He got out to check the other car and then went back to tell his daughter to get out while they waited for the police and realized she was not responding. They never revived her. Turns out she died of a broken neck from sitting sideways when hit, our necks just don't have enough side muscles to hold up in even a minor accident. He was devastated as you can imagine. He knew Ihad the same truck and 2 daughters about the same age that rode with me daily, and called me the night of accident long distance. He begged me to get rid of the truck so the next day I traded it for a full-size F-150, and drove it to her funeral a few days later. These full size trucks suck gas but I don't care, won't ever go back to a smaller vehicle even though my daughters are now 20 & 22. They also drive full size SUV's, none of us are comfortable in anything smaller.