Thank you all SO much, ladies.
JAileen, ADORABLE.
Marianna, your info was BRILLIANT, and Gertrude is a sweetie deluxe. She is Sam's inspiration. (I see you lifted Gertrude up to the window anyway!).
ClaraT, Yorkies are 100% hypoallergenic so no problem there. (Greg is allergic to many dogs too).
Aliona, you crack me up. Many thanks for your thoughtful words.
Rabbit, we've travelled with our Yorkies (Jasmine & Rosie) across the world and they had to travel in cargo - 13 years ago, they weren't as lenient as they are now with allowing small dogs in cabins. The cargo hold was pressurized and heated though. They have an area for livestock so it was fine.
As for sedatives, it depends entirely on the pet and the distance. We were advised not to sedate our Yorkies for long distances. Not sure what my vet will advise this time.