Yes, babies can fly in First and Business Class on international flights, but policies regarding "lap infants" versus purchased seats vary by airline. Most major international carriers allow infants under two to fly as "lap children" for approximately 10% of the adult fare plus taxes. Many long-haul First Class cabins are equipped with bassinets (cots) that attach to the bulkhead, though these have strict weight and age limits (typically up to 10–11kg). It is a peer-to-peer "best practice" to call the airline immediately after booking to reserve a bassinet seat, as they are limited. However, some ultra-premium cabins (like certain suites on Qatar or Emirates) may not accommodate bassinets due to seat design, meaning you would have to purchase a separate seat for the baby and use an FAA-approved car seat. While some passengers might give "the look" to parents with a baby in a quiet cabin, you have every right to be there. Just be prepared for the pressure changes during takeoff and landing, as feeding or a pacifier can help prevent ear pain for the little traveler.