Kia is Korean-made, as are Hyundai and Daewoo.
Toyota is a Japanese car, as are Lexus and Scion.
Hyundai is the parent company of Kia.
Toyota is the parent company of Scion and Lexus.
One thing that'll make this easier to understand. Look at the Kia Rio from the side and look at the Hyundai Elantra. Now do the same for the 07 and newer Kia Optima and the Hyundai Sonata and the 07 and up Kia Sedona and the Hyundai Veracruz.