Author's Note: This story was inspired by Dragon Moon by Satirrian and Another Brother by Avocado Love on Ao3. You do not have to read either of those fics to understand this one, this isn't in any way related to those stories, I just got inspired for this story while reading those. Another Brother is your typical Zuko raised by the Southern Water Tribe fic but it gave me the idea to write a Northern Water Tribe story. Dragon Moon is your usual Weredragon Zuko fic but Yue turns into a sea serpent in that story and I really wanted to write that so all credit for the idea goes to Satirrian.

The title of this fic comes from the classic poem The Tyger by William Blake.

I wrote this story from an observational perspective of the spirits. I really enjoyed it but doing so made it more of a tell than show story so at a later date I will write a version of this story written from Zuko's perspective more focused on being a dragon and growing up in the North.

Anyway, on with the story.

It was the year 83 AG, not that the spirits cared, and the dead of winter when Tui felt the spark of life appear and fall. At first, she dismissed it but it was a full moon tonight and her power was at its peak. She could afford to investigate whatever was happening in the mortal realm.

It was strange, she thought, that a new life could feel so weak and die so quickly. Normally when life appeared, it was so bright and beautiful. It was one of the reasons she liked that her original form was so high in the sky, so far from the mortals below. With the moon and the sun in the sky, she and Agni could look down at the world and feel every smallest movement under the rays of their light. This mortal, Tui knew, carried Angi's light within him but Agni was deep in slumber tonight and she didn't want to wake her brother quite yet. She could inspect this on her own.

The spark was fading fast and it was so weak she could barely feel it. Tui searched and searched the earth's surface, unable to find the one she sought, until she reached the heart of the land. Here was the last place she thought to look but this was definitely the place. Firebenders born here were always so strong, Agni's fire burning bright within them from the moment they took their first breaths. She was almost afraid to discover what had befallen this newborn.

Tui found him in a small room at the edge of the palace, far from the center of activity. Few were awake and the scene was dead silent, save the wails of a woman. Tui frowned inwardly. She hadn't seen many childbirths but she knew that it was loud. Between the cries of the child, the excited murmurs exchanged between parents, and the soft advice of the midwives, the site was typically filled with bustling life. But tonight, it was cold, hollow, and lifeless.

Tui moved closer, trying to get a better view of the people below. When she did, she saw a beautiful woman. Her hair was messy and she looked exhausted but she made no effort to fix her appearance or rest. Instead, her attention was completely focused on the tiny, unmoving bundle in her arms. Behind her, the midwives were shaking their heads and whispering hushed words at a stoic man at the doorway. He was tall and his face was strong. Tui could feel Agni's fire flowing strongly through his veins but it was clear he lacked her brother's warm heart.

She expected him to step forward. She expected him to warm his hands and try to rub life back into the child. But he did nothing. He merely turned away and walked back toward the main buildings of the palace. The woman made no move to stop him. She didn't even seem to notice.

The woman wasn't a firebender. Neither were any of the midwives. The boy was and they all knew it but none of them had the knowledge to save a dying flame. The midwives stepped away as if leaving the mother to grieve but the woman didn't give up. She shook the bundle in her arms softly, begging him to move, as tears built up in her eyes.

Tui's heart softened. She was no mother but in a sense, any child of the Water Tribes were hers. It always hurt her heart to see them perish. She couldn't imagine watching a child of her own blood die in her arms. Grief welled up inside her and the night grew colder. The midwives were gone but the woman was not alone. Tui would wait with her until Agni rose to welcome the new day.

Eventually, the woman seemed to realize her efforts would do nothing and she stepped out of the small room, her gaze turning to the sky. For the first time, Tui got a clear view of her face and noticed the hair piece atop her head. This woman was a Fire Princess. The boy in her arms was a prince of the Fire Nation, a son of Agni with a direct bloodline to his beloved dragons.

"Spirits," the woman murmured so faintly that Tui thought she was imagining it. "Spirits, Agni… Tui, La, anyone. Anyone that can hear me, please. Don't take my son from me."

And with that, a surge of determination overtook Tui. Her consciousness surged high into the sky, rising all the way to the spirit realm, where she called out for the other Great Spirits. Her brother, her husband, their subordinates- anyone who would listen to her call and come to her aid.

And come they did.

Agni's brilliant, fiery spirit arrived first. Tui couldn't describe his form, the way spirits presented themselves was incomprehensible to the human mind, but she could safely say he radiated power in a way that could only evoke awe. Her brother could help and that was a massive comfort.

Her husband came next. La was almost the opposite to her brother. Tui could really only describe him as deep. Deep and dark in that calm, comforting way the sea could be. The ocean was powerful as well but not like Agni. He wasn't nearly as awe-inspiring as the sun but he could pull on the hearts of spirits in the same way.

Soon after their arrival, the underlings of the sun and the sea gathered around.

Tui's beloved Mother of Faces and her loyal Wolf Spirit, La's cherished Tienhai and the lovely Painted Lady, and Agni's trusty Blue Spirit and steadfast Kemurikage all gathered around the great trio. A few lesser spirits as well as some spirits of Earth and Air watched in the distance but didn't dare come near. The bond between Tui, La, and Agni was sacred and they dared not step in uninvited.

"What is the meaning of this, sister?" Angi asked as he approached, sounding grumpy. "The sun will rise in a few hours. This couldn't have waited until then?"

"No, it couldn't," Tui answered, her tone conveying her desperation. That seemed to catch both Agni and La's attention. "A boy was born tonight, brother, but his flame is weak. I fear he won't survive until sunrise."

"A firebender born in the winter? And during the full moon?" La mused. He chuckled. "Whichever spirit decided that must have a sick sense of humor."

Tui shot her husband a glare and he quieted with a guilty look. She turned to Agni once more and continued. "He's a Fire Prince, Agni. He carries the blood of your children. His mother, she is in pain. She asked us for help. All of us. I think we should answer her prayers."

"She prayed to all three of us?" Agni mused thoughtfully. "That is quite odd in this day and age. The world needs more people like that. Alright, I am intrigued. I will aid you."

"Thank you," Tui sighed in relief before turning to La. "And you?"

"Anything for you, my love," La promised, brushing against her affectionately. "How will we do this? You know our physical forms are quite far from the Fire Nation and Agni needs to be there to let the sun rise if the boy has any hope of living."

The Wolf Spirit let out a soft bark and pawed the ground. Tui smiled. "I thank you, dear Wolf. You're fast enough to get there in time but you're needed to guide the other spirits and I don't think the Fire Nation will take too kindly to a wolf among them."

The Wolf Spirit dropped his head and whined but he nodded in understanding and looked to his friends.

"I would like to help," the Painted Lady said, her eyes taking a playful glint, "but I think it's only fair one of Agni's lackeys should step in. The boy is a son of fire, after all."

"I'm no lackey," the Blue Spirit grunted, "but I would like to step in. It's been a long time since I've gone down to the world of man."

"I will allow it," Angi said with a nod. The Blue Spirit bowed and murmured his thanks. "I will bestow the young prince with the soul of the Blue Spirit. You will lend him your power and aid him until his time has come and you will return to me."

"Thank you," the Blue Spirit said and turned to the Wolf Spirit. "Will you aid my journey and guide me to the boy?"

The Wolf Spirit whined in acknowledgement and the Blue Spirit mounted him. The Blue Spirit gave his superiors and peers one last look, promising to return one day, and soon turned away to ride the Wolf Spirit down to the land of mortals.

Tui, La, and Agni stayed silent as they watched the Wolf and Blue Spirits race down toward the earth. The Blue Spirit's long, black ropes flowed behind them in sharp contrast with his steed's white fur. Tui willed the moonlight to give her loyal wolf a clear path and quietly bade him good speed. She hoped they would make it in time. Even the Great Spirits had a limit to what they could do.

The Wolf Spirit's paws touched the ground and the woman, still sitting on the floor clutching her stone still son, looked up. The Blue Spirit was invisible to mortal eyes but the Wolf Spirit stood out as clear as day. Blue-grey fur shining in the faint light and handsome features sharp, he watched her carefully. He remained silent and took a few long strides so he was standing over her. The woman looked up and did not flinch away. Her eyes went wide and she bowed her head in respect before offering her child to him.

"Please," she whispered. "His heart still beats but it's faint. I'm afraid he won't survive until the morning."

The Blue Spirit, silent and stealthy, slid off his mount's back and circled around to crouch behind the woman. The Wolf bowed his head and touched his nose to the child's forehead, bestowing him with a hint of the moon's power, as the Blue Spirit breathed life back into the boy. He vanished, his soul joining the other within this tiny form.

A child's cry broke the silence and echoed through the serene corner of the courtyard. Tui felt a wave of relief wash over her as the woman broke down in tears of relief. She turned away and called out into the night. "Ozai! Nurses! Come quickly! He's breathing!"

Footsteps hurried over and the woman was quickly surrounded by helpful hands but when the woman turned to the wolf to thank him, he was already gone.

The Wolf Spirit slunk back to the spirit realm and received a few words of praise from Tui. The Blue Spirit's absence was noticeable but they all knew he would be back one day. Until then, Zuko would live.

A few months later, the same thing happened again. A princess of the Northern Water Tribe was born cold and still and her father had prayed to the spirits. Like before, Tui had called upon her husband and brother to help. Once again, her loyal Wolf had taken a spirit, Tienhai this time, down to the mortals and bestowed the child with the blessing of the spirits.

This time, however, the child was born closer to home and Tui could watch her grow up. Later, Tui almost wished she couldn't but she couldn't tear her gaze away from this one.

The girl had a rather tragic beginning. Her mother died during her birth and her father was too shaken by his wife's death to care for his daughter much. He loved her, of course, tried his best, no matter how much his heart ached. He named her Yue after the moon who had given her life. Tui was proud and honored by the recognition but the Chief was soon spitting her name as quickly as he'd been praising it.

One month after Yue's birth, in the middle of the night, a bone white serpent took Yue's place in the crib.

Chief Arnook had seen it happen and he'd been terrified. The serpent had been confused by his reaction and reached for him, writing in its nest for attention. Arnook had never really gotten over his shock but he was clear headed enough to recognize that this was his child and that she needed him. He gathered up the small serpent in his arms and brought her to the tub which he filled with water and let her swim.

It was quite a sight and one Tui deeply enjoyed immensely but it seemed this wasn't something considered normal among humans. Yue was different and that would ostracize her from the rest of the tribe so Arnook hid her away until he figured out what exactly triggered the transformation.

Tui and Arnook realized it around the same time. Each night of the full moon, Yue's physical form would abandon her and the serpent would take its place. When the sun rose, she'd return to human once more. Tui was delighted at first but Arnook had grown upset and worried. Angry, Tui would say. He didn't raise a hand to his daughter or shout or so any of those awful things that Tui feared. No, he just grew quiet and withdrawn and began making plans to keep his daughter hidden every time the full moon claimed its place in the sky.

Tui watched her grow into a bright, happy young child but those nights she became a serpent always pained Tui to watch. As she grew, it became harder and harder for Arnook to keep her hidden. She was strong in her beastly form and the water of a bathtub wasn't enough to keep her satisfied. Arnook had waterbenders build her pools deep in the back of the palace but even those were too small. Man-made solutions weren't going to last forever.

"Why can't I go out to the ocean?" Yue asked one night while sitting at the poolside with her father, waiting for the sun to set. "You let me go all the time during the rest of the month! Even just outside to the canals. I promise I'll stay away from all the other sea serpents."

"The other se-" Arnook cut himself off, pain washing over his face, as he gathered young Yue up in his arms. "Oh little moon…"

Yue blinked her wide eyes in confusion but accepted the hug and rested her little face on her father's shoulder. "Daddy? What's wrong?"

Conflict danced in Arnook's eyes as he settled Yue down on his lap. He took a deep breath and was quiet for a moment, trying to find the right words. "Yue… Oh, where to begin… You remember when I told you why you don't have a mother?"

Yue nodded, realizing how serious the coming conversation was. "Mm-hmm. Making me was really hard and she got really tired so the ocean took her away to rest."

"He did," Arnook told her with a nod, tears prickling in his eyes at the memory of his wife, "but you were really tired too."

"I was? I don't remember that," Yue responded in that blissfully ignorant way only children could be. "So how come La didn't take me away to rest with mommy?"

"He wanted to but his wife Tui said no," Arnook answered. His eyes were watering heavily by this point but he didn't let the tears fall. His voice remained strong and he lowered himself to meet Yue's eyes. He needed to tell her this and he wasn't going to look away. "Tui sent a spirit down to help you."

"A spirit? What spirit?"

"A wolf."

"Like a wolf warrior?"

"Yes but this wolf wasn't a warrior. He was a healer. Maybe a guide, I think. I'm not really sure," Arnook admitted, voice faltering for a moment but his tongue quickly picked back up. "Anyway, he touched you and your heart got stronger and you started crying. I picked you up but when I looked up, he was already gone. I thought I'd imagined it but, well…"

Arnook ran a hand through Yue's pearl white hair. She frowned and touched her own hair like she didn't understand. "So the moon… She's why I turn into a sea snake?"

Arnook nodded. "No one else can shift like that, Yue. That's why we hide it. People might be afraid if they knew."

"But I'm not scary!" Yue protested and Tui felt something inside her break a little. She got to her feet and threw her arms around her father's neck. "Daddy, please tell them I'm not scary! Unless… Do you think I'm scary?"

"Oh, little moon," Arnook said, wrapping his arms around her as the tears in his eyes finally fell. "I could never be afraid of you. But the tribe… They already disapprove of you. They want me to have another heir or arrange a m- Well, that doesn't matter right now. They don't know you like I do. They don't know you could never hurt anyone."

"I'm just a kid," Yue said quietly.

"I know, little moon. But what about when you get big?"

"When I get big?"

"You're already as big as me when you turn into a sea serpent. What about when you-"

Tui couldn't watch this anymore. She let the moon rise and beams of moonlight trickly through the windows, washing over Yue's fair skin and letting it turn to scales. Her body grew thinner and sleeker and soon her human form was gone and a serpent was slipping into the water, away from Arnook's gentle embrace.

Arnook let himself go and buried his face in his hands as Yue swam and danced in the water. Tui felt a pang of sadness and pulled away from the scene, her consciousness drifting back to the spirit world to meet with her brother.

It was always a strange transition between the two realms but she hardly noticed it anymore. Making a beeline to Agni's resting place, she woke her brother. "Agni!"

"Wha- Oh. It's only you, Tui," Agni grumbled, waving his sister away. "Leave me alone. The sun just went down. Night is your time to take over the sky. Go away."

Tui ignored him and settled down beside him. "Agni, have you been watching Zuko?"

"Who?"

"The Prince that Blue is watching over."

"Oh. Yeah. Why?"

"Is he… Does he turn into a serpent on the full moon?"

"A serpent? No, of course not," Agni scoffed. Tui felt a flash of relief before he continued. "We bestowed the Blue Spirit upon him, not Teinhai. He's a son of the sun, not a daughter of the ocean. He turns into a dragon."

"...What?"

"A dragon. You know, flying reptiles that breathe fire? Tui, I really thought you would know-"

"I know what a dragon is," Tui snapped. "Why didn't you tell me?"

"Tell you what?"

"That Zuko's been turning into a dragon!"

"What's the big deal? Blue gave him a gift. He's powerful now. He's not dying anytime soon. Isn't that what you wanted?"

"I…" Tui trailed off. She felt a storm of mixed emotions inside her. On one hand, Agni was right. Zuko and Yue were powerful now. Nothing could hurt them without intervention from the Blue Spirit or Tienahi. They were safe. On the other… "They can't live normal lives now, Agni. Yue seemed so lonely. I can't imagine what Zuko is going through."

Agni merely shrugged but he sat up, showing her that he cared enough to really listen. "Humans are cruel but the Kamikurkage tell me the most special humans are filled with love. They'll find people who accept them one day, Tui, and finding those humans will be worth all their time alone."

Tui was shocked by Agni's rare display of empathy. "You're right… You're right, Agni. They'll find friends one day. And until then, they have their families to care for them."