"Mommy, Momo made a poopy diaper!"
"Tenzin, sweety, Momo isn't wearing a diaper."
"No Mommy, Momo made a poopy diaper on the grass!"
Katara smiled at her son. "I think you have the words a little mixed up. You can't have a poopy diaper without a diaper. Otherwise, it's just poopy."
"Okay," was Tenzin's quick reply. Whether he really understood would be for time to tell.
Katara picked the child up and carried him back to the village. "Anyway, we don't have to worry about Momo's bathroom habits. He'll bury it and then come find us. He's a very clean animal."
"Because he licks himself?"
"His fur, yes. That's how lemurs stay clean."
"Does Appa his lick his fur?"
Katara smiled, imagining the sight. "Have you ever seen him do that?"
"Noooo," was Tenzin's reply, although his ambivalent tone seemed to indicate some residual fascination with the idea.
"Appa needs us to give him baths when he's dirty. And isn't it fun when we all work together to wash Appa?"
Tenzin giggled. "You make the water shoot up like a splash!"
Katara couldn't help but be delighted by her son's grinning face, and she never would have wanted to resist. She tickled a finger against his chin, eliciting even more laughter. Just by living, her son brightened her life in every way. It was like having an older brother, except completely the opposite in every way.
Katara carried Tenzin into the resort town of Su Ok Village. Built on either side of the river with the same name, the two halves of the village were connected by a lavish spa, built on top of sturdy wooden bridges extending over the rushing waters of a beautiful waterfall. Situated right on the Earth Kingdom's Western coast, the river was usually calm and constant enough, but a freak thunderstorm in the mountains had overfilled the river to the point of flooding, and the village and (more importantly, to many) the spa were in danger of being swept away.
Good thing the Avatar and his Waterbending Master (and wife) just happend to be in the neighborhood. The river had been taken care of days ago, with a minimum of soaked underclothes, and now Aang, Katara, and their son Tenzin were enjoying the hospitality of the locals. In terms of enthusiasm, it wasn't quite at Kyoshi Island levels, but it was close enough, and it featured massages and fancy robes instead of clinging groupies and Sokka in drag.
Katara found Aang leaning over one of the hot springs. Cherry trees clustered around the dug rock, giving it a natural sense of privacy. "Aren't you supposed to be sitting in that?" she asked.
Aang turned to her, a grin lighting up his long face. "I was, for a while, but then I realized I could heat up it some more with the Steam Breath move that Zuko showed me. I, uh, got a little carried away, so I had to hop out before I boiled myself. I was just about to try cooling it off with the Frost Breath trick you like to use, but... well, I haven't practiced it much."
Katara nodded. "Allow me." She set Tenzin down, then inhaled deeply, and set her arms straight down at her sides with her palms open. She exhaled, and raised her arms up and out in sequence. The air she expelled through her lips was tinged with cold, but the stunted motion of her arms kept it from building up too much hunger for heat. It became a cool breeze that easily brought the boiling tub of water to a more manageable temperature.
"Nice," Aang whistled.
Tenzin clapped, and hopped in place. "Now I try!" Before either parent could react, he sucked in as much air as his little lungs could hold, and blew it out as hard as he could while waving his arms frantically. Normally, such an action would have been adorable.
Tenzin, however, had already proven himself to be a naturally talented Airbender. He also, in Katara's motherhood experience, had a healthy set of lungs.
The summoned wind sloshed a wave of water out of the hot spring and all over the cherry trees. Katara felt her hair whipped across her face, and her skirts snapped in the breeze. Seeing Aang standing steadily against the wind, she began to understand why the Air Nomads had all shaved their heads. "Tenzin, dear, calm down! You're going to make a mess!"
Aang reached down to pick his son up. "Good strength, though! Keep working on that, and you'll be kicking tornados around in no time!"
Tenzin squirmed and made a face. "Down!"
"Okay, down you go." Aang ran a hand over his bald, tattooed head, and then his eyes lit up. "Hey, why don't we practice a few Airbending forms together? Tenzin can get a little more control over that type of thing if he knows the proper movements, and he's about the age when I started getting my earliest lessons." At Katara's look, he continued, "Nothing strenuous or dangerous, of course. Just a little exercise and a few lessons on moderation."
"Okay," Katara nodded. "That sounds good. We might as well start him on something before his uncle starts pushing boomerangs into his hands. Mind if I watch?"
"Of course not." Aang looked down at Tenzin. "Ready to learn some bending?"
"Great! Okay, first put your feet like this. Lean a little bit on this foot here, and keep your back straight. Got it?" Looking at Tenzin's stance, Aang reached over to manually nudge the child's body into the proper position. "There, that's good. Now, put your arms like this." Aang held his left arm extended from his body, the palm open loosely, while the right arms was held close to his chest and angled downward, the palm open a little wider than the other. "Keep your muscles loose, so that you can move your arms in circular motions."
Tenzin just stared. "What's that mean?"
"Here, I'll show you." Taking Tenzin's hands in his own, Aang held them in the right starting position. "See, you put your arms like this, and then, as you walk, you move them around like this." Keeping a hold of Tenzin's hands, he moved them in precise circular motions, so that one hand was always out in front of the body, and the arms provided both high and low defensive coverage. "See, this is the foundation of all Airbending moves. Now, if you move like this, and feel the power of Air in you, you can bend like I do. Try it!"
It actually took a few tries, but as he moved his arms, Tenzin became surer of the motions, and at Aang's direction, moved one hand out sharply in a move that produced a light gust of Air directly from his hand.
Katara clapped. "You did it!"
Aang was smiling as broadly as his face would allow. "That was great!"
Their son, though, didn't look happy. "That's not the right one."
"What do you mean?" Aang asked.
"I wanted Water! Not Air."
Aang and Katara exchanged a glance. "But you're an Airbender, honey," Katara said gently.
"So is Daddy, but he bends Water!"
Another parental exchange of glances, this time more worried, commenced. Katara spoke again. "Daddy can do all the elements because he's the Avatar. He can do Fire and Earth, too. He's special that way. You know I only bend Water, and Uncle Zuko and Aunt Toph only bend Fire and Earth. Uncle Sokka can't bend at all. That's the way things work."
Tenzin's voice took on a growl to match his grimace. "I want to bend Water! Like Mommy!"
Aang hadn't yet given up on reasoning with his son. "But Air is fun, too. You remember how I-"
"I don't wanna bend Air! I don't like Air!" The child was almost in full tantrum mode now.
"Tenzin!" Katara said sharply. "You do not interrupt your father when he's talking to you. He was being nice, and you screamed at him. We do not talk that way."
The child looked up at his mother's harsh blue gaze, and wilted a little. To be fair to Tenzin, most of the world's most powerful benders and leaders frequently did the same. "Sorry."
"Apologize to your daddy."
Aang pulled his son towards him, letting his hand rest on the boy's back. "It's okay. I just want you to know, though, that I'm really happy that you're an Airbender. Before you were born, I was the only one. I can bend the other elements, but I was born as an Air Nomad, and I've always liked Air the best. It was lonely that way, but I love you so much, and you're the most special person in the world to me, that it means a lot that you're an Airbender like me."
Tenzin just gazed up at his father, and Katara felt her eyes fill with tears.
"Okay, Daddy, I'll try Air."
"Thank you, Tenzin."
The child nodded. "So Mommy will have to wash Appa's diaper by herself."
"...you put Appa in a diaper?"
"I'll explain later, Aang."