Six months, one year, two years... The rules change quickly when it comes to child safety. It wasn't that long ago that the American Association of Pediatrics (AAP) advised that children remain in the rear-facing position for one yer. In March 2011, the AAP extended it's recommendation to two years or until the child is no longer in the safe height and weight range for the seat. The Highway Traffic Safety Administration is similarly recommedning that children remain rear facing until they reach the top height or weight limit allowed by the car seat's manufacturer.