Originally Posted by goingsomewhere
Check with the airline. Some airlines have a max. of 1 animal per class cabin.
I believe AA policy is no more then 1 upfront and two in the back on domestic. Make sure you get a reservation for your dog but I do not think you will be flagged for having the in cabin pet.
You might end up being declined the upgrade (if it is confirmed for you) and there is already a pet in F. Honestly, I do not see many pets on the vast majority of my flights so it may not issue, then again YMMV!
Good luck.
T