Spoiler Warning: Contains spoilers up through the end of Book 3.

Disclaimer: The Legend of Korra is not mine. I'm just taking some of its characters out for a spin.

A/N: For those of you who are non-native English speakers, the title is a reference to the expression, "black sheep of the family," which is an idiom used to describe someone who doesn't fit in with their own family.

/

Bumi was excited when he found out he was going to have a little brother. His father laughed and swung him around, giving in to Bumi's demands to be tossed into the air over and over again. Aang seemed to have a grin permanently plastered to his face and Bumi didn't think he'd ever seen him look so happy. He didn't quite understand what all of the fuss was about, but none of that really mattered because his father's happiness was infectious and Bumi couldn't help but share in his excitement.

The first indication that things were about to change arrived in a small, neatly wrapped box that an air acolyte handed his mother. A very pregnant Katara sat with Bumi and Kya as they ate lunch, occasionally pausing to scold Bumi and tell him that his food was supposed to go in his mouth, not his sister's hair. An acolyte shyly poked her head into the room and announced that she had a delivery for Katara. Bumi watched curiously as the acolyte placed the box next to Katara and opened it for her. She peeked inside and withdrew a tiny set of saffron robes.

"Avatar Aang requested that we make several sets of robes for the baby," explained the acolyte.

"Of course," said Katara. She smiled at the acolyte and put the robes back in the box. "Thank you."

There was something about the tone in her voice that struck Bumi as odd, but his concern was immediately swept aside when he felt a sea prune slide down the back of his shirt. He yelped and Kya started giggling. Bumi ran after her when she bolted and jumped through the window, leaving behind the robes and his mother's forced smile.

/

"Mom?" Bumi reached up and tugged at his mother's sleeve. "Mooooom."

"Yes?" Katara continued bending water into a row of clay jugs with her free hand while her oldest child clung to her.

Bumi waited until she paused and looked down at him. "When am I going to learn to waterbend?" he asked. A troubled look flashed across her face and he suddenly felt uncomfortable. "I mean, Kya's only five and you're already showing her how to waterbend. I'm almost eight. When's my turn gonna be?"

Katara suddenly knelt beside him and pulled him into a tight hug. "I can't teach you to waterbend, Bumi."

A dull feeling settled in his stomach and he squirmed a little. "Then is dad going to teach me how to be an airbender?" he asked hopefully. Deep down, he already knew the answer to his question, but maybe the world would make an exception, right? Maybe if he tried hard enough…

"Oh, sweetie." Katara smoothed his unruly hair. "People don't learn how to bend. Some are born with the ability to bend, but most aren't. You know that."

"Yeah. I know."

/

Bumi climbed his favorite tree and crawled out onto a sturdy branch. He could see the meditation pavilion from this vantage point and it was still early enough in the morning that the only people in sight were his father and Tenzin. He studied the way his little brother mimicked their father's perfect posture. Straight-backed, shoulders relaxed, legs neatly folded so that his weight was evenly distributed. Tenzin was the mirror image of his dad. Except that he was smaller. And beardless. And didn't have tattoos. But a mirror image nonetheless.

The twelve-year-old scowled. He tried meditating with their dad a few times before, but he could never seem to sit still long enough. His shoulders would grow tired and he'd begin to slump forward after only a few minutes. No, meditation definitely was not for him. Even so, there was a part of him that couldn't help but feel jealous of his brother's dedication to spiritual studies and meditation. Republic City demanded more and more of his dad's attention, and it seemed like what precious little spare time he had was almost always spent instructing Tenzin on his airbending heritage.

"Bumi? What are you doing up there?"

Bumi nearly jumped and glanced down to see his uncle's warm face peering up at him. "Nothing, Uncle Sokka."

Sokka raised an incredulous eyebrow and quickly scanned the area. "Uh huh. Sure. I'll believe that when badger moles fly." He stroked his beard and frowned. "Where's Kya?"

It was a reasonable question to ask. Bumi and his sister were nearly glued at the hip and everyone on the island knew that where there was one, the other was surely close by - along with a generous dose of mischief and trouble. Every air acolyte was constantly on the alert and those who let down their guard quickly learned their lesson. Today, however, was an exception. Bumi slumped against the trunk of the tree and let his feet dangle on either side of the branch. "She's with mom. She's supposed to start learning healing stuff today," he said.

"Ah, I see." Sokka rested his hands on his hips. "So what are you up to?"

Bumi shrugged his shoulders and tried to look casual. "Nothing."

"Nothing?"

"Yeah. Dad said he has to go into the city when he and Tenzin are done, and mom and Kya are gonna be busy until lunch," said Bumi.

"And you don't have any studying to do?"

Bumi scratched his head and looked off to the side. "Uh… no?" he lied. He saw his uncle's doubtful look and sighed. "Okay. Yes. But it's sooo boring!"

Sokka laughed. "Come down here," he said, waving an arm.

Bumi hesitated. "You're not going to make me go study, are you? I'm tired of reading stuff written by dead old guys."

"No," said Sokka. "I'm going to teach you something far more useful."

"What's that?"

Sokka grinned and jerked his head towards the water. "Well, we might not be down in the South Pole, but that shouldn't keep you from learning how to sail."

Bumi scrambled down the tree, sliding the last few feet and landing on his rump. He hopped up and brushed the dirt from his pants. "Sailing, huh?"

"Oh yeah. Sailing," said Sokka. He struck a dramatic pose. "Water Tribe style!"

Bumi excitedly pumped his fist and shouted. "Woo! Water Tribe style!" he repeated, copying his uncle's pose. "Right now?"

"Yeah, right now. Last one to the dock is a lame turtle duck!"

The young boy laughed and took off at a full run before Sokka finished speaking. He disappeared down the paved path, missing the way his uncle glanced at the meditation pavilion with a sad frown.

/

Two pairs of bright blue eyes peered out from behind a bush. Muffled giggles were quickly followed by a shuffling noise and the whispered demand for silence. The youngest member of the family was alone in the courtyard. He swept through airbending forms with ease and grace, completely focused on each and every move - and also completely unaware of his impending fate.

Bumi gestured to Kya using a series of hand signals the two had long since perfected. She nodded and spread her arms out to her sides, ready to play her part. He scrambled over to the eight large buckets that were lined up behind her. Satisfied that each one was filled with the perfect mixture of water and dirt, he flopped onto his belly and crawled to the edge of the bushes. He gave Kya one last look. She winked. Game time.

"Run! It's the mud monster!"

Tenzin faltered and stumbled backwards as Bumi barreled into him. "What are you doing?"

Bumi clutched at his robes and shook him. "Run! We've got to run, Tenzin! It's coming!" He threw his hands into the air. "Oh, the humanity!" he exclaimed before running off across the courtyard. He heard Tenzin scream and glanced over his shoulder as a huge wave of mud loomed over him. Grinning, he jumped onto a nearby boulder and reached for the covered walkway. He swung himself up to safety just as the muddy wave crashed over the spot he stood on only moments before.

"Wahoo! Mud monster!" Kya shouted, stumbling out of the bushes.

Bumi hopped down to join his sister and the two laughed as Tenzin sputtered and futilely tried to wipe the mud from his face. "You should have seen the look on your face!" said Bumi. "Priceless!"

Tenzin rose to his feet and waved his arms. "What is wrong with you?" he demanded. The gap left by two missing baby teeth created a slight whistling sound that ruined his attempt at a commanding tone. He frowned when the older two children laughed even harder.

"Oh, Tenzin. Don't be such a stick in the mud," said Kya.

Bumi paused and looked at her. "Stick in the mud?! Spirits, that's perfect!" He doubled over in laugher and tears blurred his eyes. Suddenly, a blast of wind hit him square in the face and he staggered backwards.

"Stop it!" shouted Tenzin, stomping his foot. "Why do you have to be so… so stupid?"

Kya crossed her arms and pouted. "Sheesh. Relax. We're just having fun."

"Yeah. It's no big deal," said Bumi. "Besides, you need to lighten up a little. You're way too serious."

"I'm not too serious. You're just ridiculous," insisted Tenzin.

Bumi rolled his eyes. "Right. I'm ridiculous." He waved his arms around in an impression of an airbending form. "Look at me. I'm Tenzin. I'm boring and don't know how to have fun."

"Oh yeah? You're just jealous because you can't airbend," Tenzin huffed. "You wouldn't understand."

Bumi stiffened and Kya glowered at her little brother. Bumi forced himself to shrug nonchalantly. "Fine," he said. "Whatever. Go back to your boring airbending. I have better things to do with my time."

He strolled off, refusing to let his brother and sister see the hurt in his eyes.

/

No one could recall a time when Aang didn't get along with his brother-in-law. That was why Bumi was shocked by his father's outburst on his fifteenth birthday. Aang waited until the party died down and most of the guests left before motioning for Sokka to join him outside. Curious, Bumi slipped out of the dining hall and followed them. He rounded the corner and stepped outside. The gawky teen ignored the bitter bite of the winter wind and crouched behind a pillar. The two tall figures were barely visible from his position, but he could hear every word.

"What were you thinking, Sokka?" his father asked.

"I don't know what you're talking about."

"The sword. You gave my son a sword for his birthday."

Bumi could practically hear his uncle rolling his eyes. "Of course I got him a sword, Aang," said Sokka. "He's fifteen. He's almost a man."

"The sword is not the mark of a peaceful way of life. It's a symbol of militancy. I can't have him carrying one," Aang said.

"I carry a sword," Sokka pointed out.

"That's different."

"How's that?"

"Because Bumi is my son," said Aang.

"Yes, but Bumi isn't an airbender," said Sokka. "Pacifism is part of airbending culture, but you know he doesn't take after you at all. He's not interested in pursuing the spiritual side of life. He's always been Water Tribe and a warrior at heart. If we were in the South Pole, I would've taken him ice dodging by now so he could complete his rite of passage. But I can't, so the least I can do is teach him swordsmanship."

"That's not our way of life," insisted Aang.

"If you really gave a damn about teaching him the airbending way of life, you'd take him along on those little field trips you go on with Tenzin. And Kya, too, for that matter." Sokka's angry response sent a jolt down Bumi's spine, and he imagined his father felt it, too. "When was the last time you took either one of them to the old air temples? They're not stupid, Aang. Bumi and Kya are smart kids. They know when they're being passed over."

Bumi's throat tightened. Deciding that he'd heard enough, he carefully crept back into the dining hall and forced a smile on his face. His mother noticed him sneaking in and didn't bother hiding her concern.

"Is everything alright?" she asked.

"Yeah, mom. Everything is okay." He glanced over to where his uncle's gift lay. It stood out against the small pile of nick knacks and doodads he'd been given. Intricate silver swirls danced along the dark blue scabbard and the crest of the Water Tribe stood out on the sword's hilt. It really was a beautiful weapon. If his dad wouldn't let him learn how to use it, maybe he would at least let him keep it.

Katara's gaze followed her son's, then flickered over in the direction he'd just come from. "Where are your dad and uncle?" she asked, eyes narrowing slightly.

"I dunno. Somewhere outside, I guess. Uncle Sokka might've gone home." Bumi pretended to yawn in an effort to conceal his lie. "Man, am I tired! I think it's time for me to hit the hay and get some beauty rest. Gotta look good for the ladies, ya know," he said. He bent down to give her a peck on the cheek and strutted off towards the family's quarters. "G'night, mom."

She stood and stared at the door as if she was trying to make up her mind about something. "Good night, sweetie," said Katara. "And happy birthday."

When Bumi woke up the next morning, he was greeted by an enthusiastic Sokka who gleefully shoved him out of bed and all but chased him down to the training yard for his first lesson in swordsmanship. Bumi was covered in dirt and bruises by the time he sat down for lunch, and he couldn't have been happier.

/

Air Temple Island was packed. Bumi sat in the front row and loosened his collar. The press of bodies combined with the warm spring air to make the temple feel almost oppressive. He scrunched up his nose at the overwhelming mixture of incense and sweat. Kya noticed his discomfort and gave his shoulder a friendly punch.

"Hey, you ready to see our baby brother get his tattoos?" she asked over the din of the crowd.

"Sure. Are you? He'll be a master airbender. It'll be even more difficult to boss him around," he teased.

Kya rolled her eyes. "Only because you won't be here to help me," she said, keeping her voice just low enough to avoid being overheard.

Bumi picked up on the anxiety she attempted to hide behind her humor. "I'm joining the United Forces. It's not like I'm leaving forever."

Kya squeezed his hand and it suddenly felt like they were little kids again instead of two teens creeping up on twenty. "When are you going to tell mom and dad?"

"I'll tell dad sometime later this week. I don't want to ruin the mood, you know? I mean, Tenzin's only going to get his tattoos once." Bumi threw a sidelong glance at his mother. "I think mom already knows. If she doesn't, she at least knows something's up."

"Figures. Can't keep a secret from that woman. I swear, she has eyes and ears everywhere," Kya mumbled. She shifted uncomfortably and tugged at her formal Water Tribe dress. "Dad's gonna flip, you know."

Bumi shrugged. "He'll get over it eventually. Maybe he'll even be happy about it. You know, since I'm going to go out and keep the peace an' all that. Besides, I'll get to wear a uniform. How cool is that?"

"Yeah. Cool. Uh huh. If you say so…"

Bumi gave her a playful glare. "Oh yeah? Well what are you gonna do? Any ideas yet?"

Kya lifted her shoulders in an echo of his own shrug. If looks didn't give anything away, their shared expressions would be enough to tell people the two were related. "Travel, probably. I'd like to visit Foggy Swamp and meet the waterbenders there. Maybe pick up on some of their tricks. Do some meditation. It would be pretty cool to check out the banyan-grove tree." She tiled her head to the side thoughtfully. "I don't know. When I think about the future, I can't picture being tied down to any one place, much less a specific career."

Bumi chuckled. "Such a free spirit. Sometimes I wonder which one of us kids is the real airbender."

A concerned look flashed across his sister's face. She looked up at the platform and saw their father off to the side, directing a couple of acolytes to make a few last-minute adjustments for the ceremony. "He does love us, you know," she said.

"Sure. I know."

/

Bumi walked out into courtyard and stared at the statue of his father that all but glowed against the backdrop of Yue Bay's dark, choppy surface. He absentmindedly reached out to pat Bum-Ju on the head as the spirit fluttered up to him. Bum-Ju's companionable presence reminded him of Tenzin's admission that Bumi had a natural connection with the spirits even before he became an airbender. He felt a pang and looked back up at the statue.

"Hey, dad," he said. "I figured you already know by now, but I'm an airbender. Crazy, huh? Oh, and the spirits seem to like me, so that's pretty cool." He paused and scratched his head. "Still not very good with the whole meditation thing, though. Why is that?"

Bumi hesitated as if waiting for a response, then waved a dismissive hand.

"Anyway," he continued, "I thought I should tell you that even though I didn't exactly follow in your footsteps, I did do my best to try to make the world a better place - just like you wanted. I'd like to think I did some good. And now I'm helping rebuild the Air Nation." Bumi tugged at his beard and stared off into the distance, "Now if only I could convince Tenzin that I really did win a boulder-throwing contest with that earthbender…"

Bum-Ju fluttered up into his face and squeaked.

"I don't know, Bum-Ju." Bumi sighed and leaned back against the same pillar he'd hid behind nearly forty years earlier. He glanced at the statue, then back at the spirit. "Do you really think he'd be proud?"

Bum-Ju squeaked once more and buried itself in the crook of Bumi's arm.

Bumi smiled, turned on his heel, and strolled back inside. "Alright then. Let's go see if the kids are ready for a bedtime story from ol' Uncle Bumi!"

/

A/N: This is something i've wondered about since Bumi's first appearance. He strikes me as a tragic character with a complex backstory. Imagine what it would be like to be the only non-bending child of two world-famous benders and war heroes. Bumi wouldn't have grown up feeling special. In fact, he probably felt incredibly inadequate. On top of that, it's obvious that Tenzin loves his family but still looks down on his older brother. There's clearly a much stronger bond between Bumi and Kya because they both grew up knowing (or at least feeling) that their baby brother was Aang's favorite.

Bumi probably was an energetic, adventurous kid to begin with, but it isn't a great leap of the imagination to think that he'd eventually become overly mischievous and rambunctious because it was a way to get attention. Over time, that behavior became part of his identity. He was Bumi, the Madman and unorthodox Commander of the Second Division of the United Forces. Even as an adult, his desire to impress his dad - to be special - never truly faded and it's implied that Aang passed away without letting Bumi know that he was proud of him (which i'm sure he was). To me, this is far worse than Tenzin's worries about whether or not he was able to live up to his father's legacy.