Hi @MissIcewolf - I just tested this in a game that has all packs except Luxury Stuff & Fitness Stuff, no cc or mods/never used. I used a household with 4 pets and was able to change to FPV on each of them using the arrow keys as you suggested. None of the displays were upside down. (probably not the issue, but just in case - is it possible your pet was lying on their back or rolling over?)
I just tested this (since I happened to finally move in a household I downloaded from the Gallery a while back), and I believe the upside-down thing may indeed be caused by the pet lying/rolling on its back.
The first pic show's the kitten's POV when I switch to it in First Person; the second pic is of the view after it corrected itself (manually moving the mouse also allows a right-side up perspective; sorry about the body clipping there, by the way!); the third pic shows the kitten's position in the usual third-person view (note that she's rolling around on her back).
I'll have to do more testing with the kitten right-side up next time I play, though.
EDIT: I did end up doing more testing a while ago. When the kitten is standing, the POV is right-side up. However, I also discovered that moving the mouse, I could spin the camera around in a way that I can go upside-down and right-side up. Since I can't attach more pics due to the limit, however, you'll have to try this for yourself. 😉
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