There isn't a specific Missouri law that dictates when you need to replace your existing car seat with a newer, better model. According to the NHTSA, you should always replace a car seat after a mild to severe crash. This is because you want to make sure that the system can still offer ample crash protection to its tiny passengers, and if any of those materials are compromised, it could render the seat unsafe. If your vehicle is involved in a minor crash, then you don't necessarily need to replace your car seat automatically. Still, it's a good idea to take it to a car seat specialist in your area who can assess its overall condition. The NHTSA defines a minor crash as one in which: • You can drive the vehicle away from the crash site • The door nearest to the car seat was not damaged • The airbags (if available) did not deploy • The car seat does not appear visibly damaged • No one involved in the crash was injured Even if you aren't involved in a crash, it's still smart to replace your car seat within six years of its manufacture date. Newer models will feature advanced, upgraded features that can keep your little passengers safe.