Disclaimer: I don't own Avatar: The Last Airbender, its concepts, or its characters. No money is being made out of this.
A/N: This is a Firefly crossover.
Katara was not comfortable with the idea of a Fire Nation man on their ship, doctor or no.
"Look, he's a paying passenger. You know we need the money," Sokka had said.
Aang liked him, but he liked everyone. Suki and Toph were indifferent. But Katara knew he had something to hide. Why would he be on Serenity otherwise?
So, she snuck to the cargo bay and opened the giant box he'd brought aboard. Her scream attracted the entire crew.
"What the hell is this?" she demanded.
"This," he said, putting himself between her and the box, "is my sister."