Moulded Child Safety Seats

  Well it's a simple idea and i am not sure if it hasn't been tried already or not (maybe someone can tell me).
  Basically it is a child safety seat that is moulded into the passenger seat of a family car. But can still be used as a normal passenger seat for adults (removable cover). I am sure it could be a valuable feature to sell cars with this built in them as an option.