Originally Posted by
esofina
I'll be traveling with a 2 month old soon, gotta get that expedited passport

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CO policy is that lap children are free on domestic flights, and 10% prevailing fare on international flights, so what gives for domestic portions of international trips?
I have experience with this. My wife and I took our 11 month old daughter as a lap child to Australia a number of years ago. We flew Delta from Boston to LAX, then Qantas (QF) from LAX to SYD. We made a lap child reservation for her with QF (under a separate PNR) and paid 10% of the adult fare from LAX to SYD on QF. She received a QF boarding pass. We did not pay for the child on the BOS-LAX flight, and she did not have a boarding pass for the domestic flight.