To add to what Duane Veatch said, pets can only be taken on Amtrak trips of up to 7 hours at most, and you can ONLY ride in coach but not sleepers, business class, or any other first class accommodations. The maximum weight of your pet plus carrier is 20 pounds, and each passenger can only have 1 pet with them per reservation. If a separate person traveled with you, they might be able to book a pet reservation for your 2nd cat. If you want to travel further you could travel up to 7 hours away (i.e. Minot to Havre), stay overnight there at a pet friendly motel/hotel there, then travel further the next day (i.e. Havre to Whitefish). You can FULLY read about their pet policy here: https://m.amtrak.com/h5/r/www.amtrak.com/onboard/carry-on-pets.html
Only if they are seeing eye cats or if you pay the pet fee and have them contained in carriers.
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