I understand. [He whispers softly, with something like a crackle in his voice. He almost made the decision with his own letter, but he ultimately read it. He had to make sure that the letter wasn't actually just a note that she was off on some unexplained trip. He feels it all over again, now, just the absence of that little airbender.
[ action ]
So Aang gently wraps her in a hug.]