It was a different matter the couple of times we boarded the brood at our local Cat Clinic when all of us were going to be away for a few days. Once they got used to it, they did fine being boarded there, but man, were they happy to see us return.
The winner for me, though, was the day I had proof that our animals do not just identify us through smell, as some would have you believe. The last time we boarded them, in 2015 when the three of us were in Florida, Poe had had a strong reaction to being taken there, and we sat with the three of them for a long time waiting for him to calm down and stop hissing at us and Kali and Mikey in the little room they were assigned. (It's a very well done boarding facility in all respects.) The next day I called to see how they were doing, and the vet told me they finally gave Poe his own room because he was stressing out the other two -- but they were all doing fine by that point. And it was fine the rest of the week. The evening we got back to pick them up, I went to Poe's room and looked at him through the window before going in. He was lying there calmly, no problem. Then I tapped on the window to get his attention, and he literally did a classic double-take when he looked up and saw it was me through that thick door and window. That was a joyous reunion all around.
But yeah, they can easily be put off for a bit when we humans come home after an absence, or when one of them is brought back after a trip to the vet. It's all normal.
