Back ground
Toph and Aang have been traveling, training, and going where the avatar is needed after the defeat of fire lord Ozai.
Katara and Zuko are together in the fire nation still in contact with the group. That's a different story.
Sokka left to wander on his own/find himself for a time. That's also a different story.
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It was nearly a year since Zuko had taken the throne of the fire lord with the help of Team Avatar. Aang and Toph had been traveling alone for about a month now.
Spotting a flat aria in the stark desert like savannah Aang guided Apa toward it. Wood was nowhere to be found so a fire wasn't going to happen so they ate dried food while they talked about bending and old memories.
"See ya in the morning Twinkle toes" Toph said as she got in her earth tent.
Aang laid down on Appa and stared up at the sky eventually falling to sleep in that position.
The temperature rapidly fell and Aang found himself getting as close to his bison as he could to stay warm. at some point he awoke and found himself wondering how toph was doing in the cold. He found her shivering against the cold, which he did not expect from the stoic earth bender. He reached out, felt her arm, and understood why she was shivering. He dragged her from the earth tent over to where Appa was, waking her in the process.
"Aang I'm f-fine, really."
"Don't argue." was all that he said, and surprisingly she didn't
Aang laid her against Appa's stomach and laid down on her other side in order to fend off the hypothermia. In about twenty minutes the shivering had completely stopped. Twenty more minutes, and they where both fast asleep.
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In the morning Aang woke to see Toph already awake sitting to his right looking at the sky with eyes that didn't see.
"How do the birds do it?" she asked not moving any part of her body but her mouth.
"Do what?"
"They are so small and fragile, yet they survive the cold each night, and happily sing there songs the next morning."
"That's just what they are supposed to do. Humans aren't supposed to sleep outside without a fire or blankets or something like that."
"Your right, guess we need to get blankets at the next town we get to."
Having not found a village before stopping for camp both Aang and Toph slept next to/on top of Appa. By the time they reached a village, the need for blankets was forgotten.
End of part one