Hello there!
Katie would have to report this and also have it written on on her (tax return) statement. The reason why she would have to do this is because if she were to do that she wouldn't be stealing money pratically.
She would be experiencing a (gain) of money. The reason to why she would be experiencing this would be because first she bought the car originally for 25,000 and she is now selling it less than for what she bought which means she is getting he me taxes for the 25,000 and not only that,but she ifls also getting a 12,000 from selling her car.
So, Katie would be experiencing a great time with all of this money that she would be having. She vet's here taxes and her money for the car.
She would be getting a (gain).