Seat belts are designed to safely secure one passenger in the event of an accident. Sharing seat belts is not an appropriate practice to keep children safe in a car.
It should be noted that all states and the District of Columbia have child passenger laws requiring children to be properly secured in either child safety restraints or seat belts while in a motor vehicle. Laws detail what types of child safety restraints are required depending on a child’s age, weight, and height. Most states allow children to use adult seat belts once they reach a certain age or at least 57 inches in height. Ages can range from 5 to 9 for children to use a seat belt without a car seat or booster seat.1