Apparently, Kristin was carrying her pup onto the plane when she was confronted by a "verbally abusive" supervisor who said she didn't have the correct paperwork. Eventually - after Kristin burst into tears - airline officials realized they were in the wrong and allowed her to board the flight, with her dog in tow.
Kristin later tweeted, "American Airlines: Dallas flight attnt supervisor Ms. Kidwell. Abuse not okay. #tripfromhell."
A rep at AA told TMZ, "We have been in touch with Ms. Chenoweth to offer our apologies for the misunderstanding. We refunded the [$125] cabin pet charge as soon as we realized the mistake. We hope she will consider flying American again in the future." There's no official word from Kristin about whether or not she is taking them up on their offer but, based on her Tweet, we're thinking the answer in "no".