Day 1:

Sometimes great ideas came to her when she least expected them.

Usually, they were helpful, like when she had the idea to install wind turbines on the Bounty's hull so they wouldn't use so much gasoline, or when she realized she could manipulate the humidity in the air with her elemental powers so that it wasn't always so freaking dry in the winter.

But sometimes, when she was feeling extra mischievous, she could come up with some great spontaneous pranks to pull on the other ninja. So when she walked into the game room at the monastery and noticed Kai's BorgPhone lying, unattended, on the coffee table, she knew she couldn't just leave it there. It wasn't quite April Fool's Day yet, but he had eaten the last two Girl Scout cookies, so it wouldn't be completely unrequited...

Oh, who was she kidding? This was her brother she was thinking about, she'd never pass up on an opportunity to troll him. Besides, he goes into the city and leaves his phone behind? He's practically begging to get pranked.

Doing a quick peek into the courtyard to make sure no one was nearby, she reached out and snatched up his phone. Hastily opening the phone app, she went to his 'Recents' page and scrolled down until she found her number. Jay had taught this trick just a few weeks ago after he had accidentally done it to her phone while helping her set up a tracking app. Nya's fingers flew over the screen as she remembered Jay's lesson, her thumb hovering momentarily over the 'change ringtone' button before she decided, "why not?" and pressed it. She scrolled through his music library, looking for something that would annoy him the most...

There. Why did he even have that song anyways? Kai hated Justin Bieber.

Nya felt a grin growing on her face as she closed the app and set her brother's phone back on the table, making sure it was exactly how he had left it. Success.

She heard a dragon land in the courtyard outside and quickly darted out of the room, knowing that if Kai caught her in here her prank would fail and it would all be for nothing. She sauntered down the hallway towards the kitchen, where she could hear the voices of the other ninja spilling out. Behind her, she could hear the slight hissing of the bamboo screen door as her brother entered the game room.

Nya smirked, knowing that in a few hours, the usually calm monastery would be full of chaos and one very confused fire ninja. Her plan was underway.

"Nya? Did you need something?" Kai poked his head into the kitchen, a confused look on his face. Nya started, then shook her head.

"No, I don't think so."

Kai frowned. "Huh. I could've sworn you called me," he muttered as he turned and left the room. She had set up his phone to randomly get calls from hers, and apparently, he had just received the first one.

Jay looked at her, suspicion growing on his face. "You did something, didn't you?"

Nya grinned. "Remember when you were setting up that app and you accidentally made my phone get random calls from yours?"

"Yes... oh, did you do that to Kai's phone?"

"Yeah. And I set his ringtone to 'Baby' by Justin Bieber."

Jay leaned back in his chair, chuckling. "He hates that song."

Nya nodded. A silence fell over them for a while, Nya playing with her placemat and Jay staring dreamily at the ceiling. After a few minutes, he stood up. "So, you know, if I see Kai, and he happens to ask me if I know anything about this, you want me to feign ignorance?"

Nya laughed. "I mean, if you wanted to, that would be helpful."

Jay grinned. "Alrighty then. I'll spread the word."

He left the room, slipping out the door just as Kai entered.

"Are you sure you don't need anything?" he asked.

"I'm positive, Kai. Why do you ask?" She felt a smirk growing and tried to smother it. She couldn't give herself away now!

"You- you just called me again..." he said, his brow furrowing.

Nya shook her head. "Nope. You can ask Jay, he was just in here talking with me."

His eyes narrowed. "Are you sure you're not just messing with me?"

She pulled out her phone and opened the recent page on her phone app. Tilting the screen so that her brother could see, she said, "The last time I called you was three days ago, see?" She turned her phone off and put it down on the kitchen table.

Kai bit his lip. "Okay, then...". He turned to leave, but just as he was about to slide the door closed, the first few notes of Justin Bieber's 'Baby' started playing, coming from his pocket. He whipped around, pulling out his phone, and rushed back towards Nya, who was now struggling to keep a straight face. "See? It says you're calling me. I don't even remember setting that ringtone, I hate that song anyways."

Nya couldn't keep it together anymore. She burst out in giggles, covering her face with her hands as she took in Kai's bewildered look.

"Wait a minute! Did you do this?"

Nya shrugged, her shoulders shaking. She could feel tears of laughter starting to form in her eyes, and she quickly wiped them away. "I have no idea what you're talking about, Kai," she said, gasping.

He leaned down on the table, glaring directly into her eyes. "Uh huh... yeah right. How do I fix it?"

Nya smirked, her laughter dying down. "Like I'll ever tell you!"

Kai huffed. "I'll get you back for this."

"Oh, it is so on!"

"You'll regret doing this, you know. Just saying," he retorted.

She shrugged. "You'll never catch me."

"Is that a dare?" Kai slid out of the room, saying, "You'd better watch out. I'm coming for you."

Nya laughed as he closed the bamboo screen. He ripped it back open and stuck his head back into the room, pointing two fingers at his glaring eyes, then at Nya. "I'm watching you," he warned. She waved back at him, smiling. Her plan had gone exactly as intended.

The siblings' prank war had begun.

Hi everyone! Thanks for stumbling across my story and deciding to read it, I hope you were not disappointed. The next update will hopefully be tomorrow!