A/N: Okay.... yet another idea from today... well actually, I've had it for... forever almost... but I thought it was too stupid.... now I'm thinking I'll tell you all since you've been idea-deprived!
Where: A couple different places in the Avatar world....
When: a couple weeks after Aang turns 16
Summary:
After Aang goes off to completely finish all his Avatar Training, (he's 16 now!) Katara gets a letter from Zuko, (because Aang went to the Fire Nation first) that says Aang had gotten sick. Not one of the healing people from all over the Fire Nation could help him, or identify what was wrong with him. All they knew is that Aang was having coughing fits, vomiting, very high fevers, and losing large amounts of his energy fast... so he was sent back to the Water Tribe to see if anyone could treat him there. They conclude that his illness is due to the fact that Aang took on his Avatar duties too early, and that caused him major health problems...
A/N: So that's what I've come up with....... Please tell me what you think of it!