When children under 4 exceed the height or weight limits of their child seat:

• They should transition to a forward-facing child seat with a five-point harness, placed in the back seat.
  Explanation:

  "Once children under 4 years old exceed the manufacturer's maximum height or weight limits for their child passenger restraint system, they must transition to a federally approved, forward-facing child restraint system with a five-point harness, installed in the rear seat of the vehicle."
• They must not use a regular seat belt in the front seat.
• They should not sit without a special seat, even if accompanied by an adult.
• They are required to use a booster seat, ideally in the back seat.