You know, in my post about using the five-point harness in your child convertible car seat, I forgot to talk about the chest buckle. Proper placement of the buckle is important to keep your child in the seat in case of an accident.
The chest buckle needs to be at armpit level when connected. The Buckle helps to position the shoulder straps over the child’s shoulders, and keep the straps from spread apart in an accident, allowing the child to be thrown forward and possibly out of the seat.
The chest buckle on the five-point harness is usually the first one your child learns to disconnect on its own. For safety reasons, your child should be taught to leave this buckle alone immediately. One way we did this was if our child disconnected the buckle in their convertible car seat, we stopped the vehicle and turned off the engine. The car was not to start or go with anyone unbuckled. We were lucky and had to only do this a few times. Now the kids will actually start to throw a fit if the car is started and they think it might move before they are completely buckled in.