Vehicle stopped in traffic in exit lane of freeway with a line of other vehicles. Driver at-fault was traveling at freeway speeds of 65+ mph and veered into the line of vehicles waiting to exit. Our ID4 had 4 passengers, adult driver, adult passenger, and two children in rear seat, all wearing seatbelts. The seatbelt of the rear passenger's side failed resulting in child hitting their head on headrest in front of them as well as the side window and post. Moderate injuries occurred and child is recovering. None of the others in the vehicle were injured. Likely failure is pretensioner of seatbelt. Currently in the accident investigation with insurance and the component has not been inspected at this time but certainly will be.

- San Diego, CA, USA