A/N: Wrote this for 31_Days over at LJ, for the prompt Dec. 30: "I thought I'd stop and say hello."
When Aang woke up early that spring morning, he was at first confused as to what had roused him. He hadn't been dreaming, and the house was completely silent. He turned his head, half rolling over to get a look at his wife's sleeping form, but Katara was still thoroughly entrenched in unconsciousness, her side rising slowly in time with her breathing. It hadn't been her, then.
Aang's brow was just wrinkling in puzzlement when he felt it: a tap, minute but unmistakable, originating from downstairs. Coming to a realization, Aang slipped out of bed, padding into the hall and towards the stairs, stopping only to check that his son and daughter were still asleep in their rooms.P
When Aang opened the front door, he was greeted by a short, dark haired figure, dressed in traveling clothes and carrying a pack. "Hey, Toph."
"Morning, Twinkletoes," she replied, her usual smile hitched casually on her face. "What took you so long? I felt you rolling around up there for a while before you came downstairs. I didn't interrupt anything, did I?"
Aang blushed. "Oh, no, not at all," and Toph laughed at his discomfort. "I just wasn't expecting it, that's all. I mean, I haven't had much use for being able to see with vibrations since the war ended." Aang stepped out onto the porch and closed the door behind him. "So, um…what's up?" He was still mildly confused; Toph was not known for being an early riser.
"I'm leaving."
"Who the what now?" Aang said. "You're leaving? To go where? And why so early?"
"I don't know. Lately Kyoshi hasn't really been doing it for me, you know? I mean it was nice to have some place to come home to every night, but…I don't know. I feel restless." Suddenly Toph grabbed her pack and started down the porch steps. "C'mon Twinkletoes, let's go for a walk." Aang followed, realizing that he was still in nothing but a pair of cotton trousers.
They walked in silence until they reached the beach, where Aang decided to break the silence. "I take it you haven't told anyone you're leaving."
Toph snorted. "Of course not. Sokka would kill me, for one thing. Well, he'd try." The previous week, Sokka's youngest son had hit him in the head with a rock without touching it, and since then all he could talk about was how his son was going to have the World's Greatest Earthbender as his teacher.
"So why'd you tell me?"
"Because I had to tell someone. Believe me, I wanted to just leave, but…I couldn't. I don't know. I have to do this but…I know you guys. You'd make some heartfelt speech about family and shit and then I'd feel guilty and I'd stay. But I couldn't leave without saying…anything."
They'd been walking along the beach, but now they came to a halt. "So, you don't know where you'll go?" Aang asked.
"Well, I have some ideas. I'll probably end up in Omashu at some point. I still owe that old bastard Bumi a rematch."
Aang chuckled. "I'm sure he'll be glad to see you." On impulse, he rested a hand on Toph's shoulder, and she responded by hugging him tightly. "Stay safe, Sifu Toph."
"You too, Aang." They separated, and Toph resumed walking down the beach. Aang watched her until she vanished in the predawn gloom, and then he returned to his house.