If I want to book an award ticket using TK miles on TK metal, including an infant in lap, how is the cost for the infant determined? I've tried looking through various forums and haven't found a clear, definitive answer on this. From a test booking it seemed like I would be charged 10% of the mileage fare and roughly 10% of the taxes and fees, but as that was a test booking and the website clearly stated that I can't book for the infant as part of the initial booking process (I guess I can add an infant to the booking later or call/go to the airport), I'm not confident that what I saw online was actually accurate. Many programs will charge 10% of the adult fare plus taxes and fees, some will charge 10% of the miles plus taxes and fees, and some airlines have completely different rules. Anyway, if any of you know the answer to this please let me know as it would be quite helpful. Thanks!