If the airline you choose is like most airlines, you will need to book your ticket in advance, since they only take 2 pets per flight, per cabin. That is 2 pets in the economy, 2 pets in business, 2 pets in first. Also, you will need a soft carrier, since the hard ones do not fit under the seat. Most airlines have a weight limit for the pet they allow inside the cabin. You have noticed I am not mentioning anything about putting the cat in the cargo compartment.
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