I would recommend a window seat. That way, if you need to let your Yorkie pop their head out of the carrier, and you have a strict/annoying flight attendant to deal with, there is less chance of getting yelled at. Mine would yelp even on medication on a plane trip, but he was OK if I let him poke his little head out and look around. One crabby flight attendant yelled at me for letting his head out, so I learned to obfuscate her view whenever she'd come down the isle. Not hard, because the kid sitting next to me liked my Yorkie, and was happy to hold up the newspaper whenever this idiot would make her rounds... It did not matter, of course, that my Yorkie would stop barking if he could only look out the top of the carrier, this flight attendant required that he be completely inside of it, which technically is the rule. However, in my case, it was a stupid rule and you never know if you'll get a good flight attendant that will work with you to keep the peace, or a strict one that will make the flight miserable for you, your Yorkie, and the rest of the passengers that have to put up with a Yorkie barking fit
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So… choose the window seat to better hide what you may have to do.