Author's Notes: I love the childhood-friends-to-lovers trope more than I can tell so let me write another one.

There are two song mentions in this, almost in the end, and I recommend that you listen to them when the titles appear. They are 'Hopeless Opus', by Imagine Dragons, and 'Can't Help Falling In Love' (the Haley Reinhart cover/version) (the title is from this song, by the way).

He was 8-years-old when Elsa and Anna moved to the house next door.

Jack watched as Mr and Mrs Arendelle got out of the car and took the two children with them. The last time he'd seen Elsa was months ago, last summer, when she came to visit her uncle and aunt. She seemed to be taller, but he'd have to be beside her to confirm it.

But he couldn't, he remembered. He's promised to his mom that he'd give his friend some space.

It must be a terrible time for them. His mother had said. After that horrible car accident... They need some time to recover, okay?

(It was fine, even though he didn't know how long "some time" was. And, as a friend, shouldn't he be there for her?

But he didn't say that.)

From his window he could see the girls' bedroom. It was strange to see movement and light in a room which had never been used, but he didn't pry. Mrs Arendelle set a big curtain in their window anyway, so he couldn't see anything.

Jack had thought Elsa and Anna would go to school on Monday, but they didn't. It made sense, once he thought about it, but that meant they still weren't feeling better.

On Tuesday, he got really worried. And by Wednesday night, he was as stressed as an 8-year-old could be. He didn't want to talk or to play with them. He just wanted to check if they wanted help.

His mother was downstairs, so using the door was out of question. Yelling until his friends heard him and opened the window could alert the adults in both houses of his contact attempt. That left him with only one option.

Very, very carefully, he opened his window and got out, holding onto the stool while he firmed himself on the roof. Then he lowered himself to an on fours position and crawled his way to the edge.

The roof of the Arendelles house wasn't far. He couldn't reach it with his leg, so he'd have to jump, but at least he wouldn't die if he fell on the ground below. Hopefully. He was trying not to think about it.

So he just stood up and jumped.

As soon as he was on the other side, he sit down and stood there for a moment, his heart thumping. He hadn't died. Or broken his leg. Or caught the attention of his parents. He was going to be okay.

Jack made his way toward the girls' room and knocked lightly on the window. It occurred to him then that Elsa and Anna might be frightened and call their uncle and aunt instead of investigating and seeing it was just him. But before he could dwell on it, Elsa drew the curtain aside, eyes wide with fright. Jack waved hello, and she blinked twice before opening the window.

"Jack?" She whispered, confused. He hesitated.

"Hi. I just wanted to see if you're okay..." He said, his hands fidgeting. "I heard about your parents." He said in a low voice. The words felt wrong when he said them aloud, but what could he say? He was starting to understand why his mom didn't want him to see her for a while.

Elsa looked away, not saying anything at all.

"Where is Anna?" He asked, hating the silence even more than the words.

"Downstairs." She said. There was a pause.

"So, are you? Okay, I mean. Are you... okay?" Again, "okay" was the wrong word, and he already knew the answer.

Elsa opened her mouth to say something, then closed it. She looked back at him, a slight frown in her forehead.

"I'm not." She whispered, and let him in.

Jack was beginning to truly hate Snowman Attack.

First of all, it made no sense at all — a snowman with stupidly over-hyped ice powers for no determined reason. Secondly, the snowman, who was a main character, for crying out loud, had a creepy laughter and horrible one-liners. And third, even he, as a 12-year-old, recognized there was no need for more than one movie. But maybe that last reason was a result of his disgust for the character.

But Elsa loved it. And she forced him to marathon the entire trilogy with him, claiming it was part of the moral code of best friends. Or something. She just had to pout and look mildly sad, and Jack agreed to watch it.

'Snowman Attack - The Terrifying Blizzard of Death' was okay. He almost fell asleep during 'Snowman Attack - Nice Weather', and he detested 'Snowman Attack - Mother Nature's Revenge' from the very first minute.

"They're not so bad." Elsa defended when she saw him frowning.

"How can Olaf be the hero?" He argued, pointing at the television as if that'd make his point stronger. "He's the one who messes everything up in the first place."

But Elsa just nodded, delighted. "And he finds a way to fix it." She concluded.

Well. He wouldn't argue with Elsa. She usually had a point and better arguments than him, and he was tired of thinking about those movies, so he just sat back and tried to pay attention to the screen.

At least he now knew what to get her for her birthday.

The plush snowman was truly hideous. It had huge eyes and a wide smile, which made it look like a maniac psycho — which Jack still thought was the hidden message of the movies — but he didn't dwell on it. He bought the plush and the Illustrated Guide to Snowman Attack. His mother tried to convince him to take choose only one, but he insisted on buying both. Elsa would like both.

In fact, to say she liked it would be an understatement.

Elsa almost cried when she saw the abominable snowman and hugged it, then hugged Jack so tight he couldn't breath, and she refused to let go of her presents all evening. She read the book while eating cake, careful not to let any crumbs or frosting fall over the pages.

"See, mom? It was totally worth it." Jack whispered to his mom, gesturing to Elsa swooning over the presents he'd given her.

Tatianna didn't say anything for a minute, and when he looked up, he saw that she was giving him a strange look.

"I guess it was." She said, then smiled and giggled, shaking her head, and Jack didn't understand it.

(It would take him a while to figure it out.)

Within the years, the Arendelles and the Overlands grew a lot closer, mostly because Jack, Elsa, and Anna insisted in doing everything together, naturally making the families know each other better. It came to a point in which they agreed to spend the spring break together, doing a trip.

It would be fun, they said. We're going to explore new places and have a great time, they said.

They knew it was a road trip, so it would be within the country. From the way their parents talked about it, the teenagers dared to imagine Broadway, theme parks, music festivals. Famous places they'd never been in.

In reality...

"So... We're not even leaving the state?" Jack asked, incredulous. Beside him, Anna's face matched his in barely polite disapproval. "Excuse me, but what?"

"I know what it looks like. 'This will be boring and I don't want to go'." Jack's father, Edmund, said, attempting to imitate the teenager. Jack scowled.

"There wouldn't be enough time to get to know other states like we wanted." Ingrid said, smiling. "It will be nice to know the history of our home."

"It sounds fairly interesting." Elsa commented quietly from behind them, and recoiled when Jack and Anna glared daggers at her.

"Are we at least going to stop by in Vegas?" Jack asked, sounding hopeless, and Tatianna shot him an exasperated look while Edmund roared with laughter.

So two days later they left; four happy adults, two scowling children, as the others were calling them, one excited nerd and two cars. The left in the early morning, before the sunrise.

The three teenagers sat in the backseat of the Arendelles' car. Anna was fast asleep, snoring slightly through her open mouth.

Elsa sat in the middle, and Jack noticed she did her best not to look at the road ahead of her. She opened and closed apps in her phone, stared at her hands, and finally rested her head against his shoulder, trying to get some sleep.

"You okay?" He whispered to her, frowning. She was moving a lot, trying to find a comfortable position.

"No." She mumbled.

"Wanna talk about it?"

"No." She snapped in a hard voice, then shut her eyes tighter and grabbed his arm — she liked to hug things while sleeping.

Jack sighed, not making a point to be discreet. It's just... She could be so darn difficult sometimes. The little excitement he secretly had for the road trip vanished, and he didn't talk to her for the rest of the day. Not that she talked to him either. Not that it mattered, he told himself.

It was a behavior he hated, but recognized. Elsa hated being afraid. She smiled to her uncle and aunt only to take deep breaths when she thought no one was looking. Whenever they took a pause from the road she eyed the car with suspicion and hesitated almost imperceptibly before entering it again. Gradually, his anger turned to the familiar hurt he felt when she tried to isolate herself like this instead of reaching out. But he didn't say anything. Not until he saw her with two pills on her hand.

"What do you think you're doing?" He growled, forgetting about his stupid hurt and reaching out to take the pills out of her hand — which she had closed into a fist. Her eyes widened at the volume of his voice, and she glanced over to her aunt, who was a few feet away, examining an information board about a historical building.

"Shh." She pleaded, looking at him with panic. "It's melatonin. It's supposed to make you fall asleep."

"I don't care. It's self-medication, it could do damage." His voice was still angry, and he tried to control his emotions. Pissing her off wouldn't do anyone any good.

But Elsa looked so tormented that it was very easy to tone down his rage.

"I've already taken one." She confessed in a low voice. "So did Anna, but it didn't work with me."

Ah. So that's why Anna had been groggy all day and was walking around like a zombie instead of like a living person. No wonder why she fell asleep the second she got into the car.

Jack sighed, feeling exhausted all of sudden. "Okay. I get it. But," He licked his lips, trying to think of what to say. "No self-medication. I'll distract you, I promise. Please?"

It took her almost a full minute to sigh and open her hands, letting him take the pills away from her — he threw them away with relief. And then there was silence — not the good, comfortable kind, but the type that made one search in their brain for the most irrelevant topics, just to have something to say.

"Where did you even get the pills?" He blurted, mentally stabbing himself. He was supposed to change the subject.

Elsa shrugged, hiding her hands inside the pockets of her jacket. "Aunt Ingrid takes them. She has insomnia."

"Well, I'm glad they're gone." He murmured, then cleared his throat and squared his shoulders. "So. I challenge you to a duel. Flappy Bird. Who gives up first has to pay McDonald's to the other." He proposed in the most exciting voice he could muster.

A hint of a smile appeared on Elsa's lips, which made his heart throb for some reason, and she raised her eyebrows. "Flappy Bird? Seriously? How can you still have that game?" Her voice was teasing, and he grinned. Sweet, sweet success.

"What can I say? I have an old ass phone." He mumbled, not really meaning for her to hear the last part, but her eyes widened and she laughed, and he figured it was okay.

So they spent their time inside the car playing. Jack sat in the middle this time; Elsa didn't say anything, but her small smile let him know she was grateful.

Whenever she was the one playing, he would try to distract her from the game at all costs. Singing made-up lyrics in her ear, telling her awful jokes and irrelevant bits of information were his most used tactics.

"Did you know that complex numbers arose from the need to solve cubic equations? In the seventeenth century." He murmured lazily, watching with delight as the bird hit the green tube.

"Seventeenth—? Oh, sh—Oh, God. Fuck you, Jack!" She hissed so only he could hear, and he laughed out loud.

"You're such a loser." He beamed at her. "In so many ways."

"I learned with you." She replied coldly, handing him the phone with a glare so angry it made him laugh again.

When he finally lost and gave her the phone again, she hesitated before taking it and looked up at him.

"Thanks for doing this, Jack. You didn't have to. And I appreciate it." She added the last past quickly, looking away. Her face was a slightly mortified expression he was familiar with.

"You're always welcome, you know." He told her in a low voice. Her uncle and aunt were chatting lively about something and Jack doubted they were paying attention to the conversation in the backseat, but it wouldn't kill anyone to be sure they couldn't hear. Better safe than sorry. "I just... I wish you would just tell me when you need a distraction instead of, you know, running away. Hiding." He said, averting his gaze too.

"I know." She murmured after a while. Slowly, she rested her head over his shoulder and took a deep breath. "I'll try."

There was silence for a moment.

"Hey, I'm sorry... I'm sorry for yelling at you." She blurted, guilt clear in her voice. Jack smiled a little.

"You call that yelling?" He said softly, and she knew she was forgiven.

"It's, you know." She gestured vaguely to their surroundings. The road.

"I know." He assured her. "Do you think, maybe, talking to someone would help?" Jack murmured, frowning. "I mean, they are planning to make this an annual event." He added, pointing to her relatives in the front seats. He heard her sigh again.

"Maybe." She murmured, and by the tone of her voice, it wasn't a discussion she wanted to have right now. Later, then. "Okay. This time is for real." She turned on the phone screen and pressed the play button. "I'm kicking your ass, you'll see. You're paying me McDonald's."

He chuckled, and leaned his head so it rested on top of hers, a pleasantly warm feeling arising in his chest. Maybe the trip wouldn't be so bad after all.

Becoming an adult was exhausting and he wanted to stop. Jack stumbled into his room and fell over his bed, lying there for a moment before sitting up. The music coming through his earbuds was loud and perfect for brooding over the weight of life.

At least, at least, his exams were finally over and he could get some sleep over the weekend. He silently thanked the humans who came up with a time system in which Friday existed.

More out of habit than anything, he looked up to the window next door, absentmindedly, and his eyes fixed on Elsa.

She was moving strangely around her room (dancing?), an almost empty water bottle in left hand serving as a play-pretend microphone, while the other hand cheered an imaginary crowd. Her lips moved accordingly to music he couldn't hear, until he took off his earbuds. Jack recognized the rhythm of an Imagine Dragons song, and Elsa's painfully horrible singing voice above it. He pressed his lips in an attempt not to laugh, and failed miserably.

And then, to his eternal amusement, she opened her eyes and looked at him. She froze for a second, surprised, then laughed along with Jack.

Elsa beamed and opened her window, which made him recognize the song — 'Hopeless Opus'.

"Come over here, mister." She called, the smile never leaving her lips. There was an exceptionally happy twinkle in her eyes.

"I prefer to stay away from your lethal voice, thanks." He replied. Elsa pouted, pretending to be hurt.

"Rude. Come on! I'm all alone." She sang the last part, raising her eyebrows suggestively, which made Jack laugh and his heart ache — out of habit, he ignored it.

"Oh, how tempting." He mocked, but got out through his own open window. Jumping toward Elsa's roof was so familiar he couldn't even believe one day he had feared doing it.

Once he was inside the room, Elsa just grinned. She resumed her horrible singing from the top of her lungs, and he didn't even wince — just smiled. She didn't seem to like it.

"Sing with me, airhead." She commanded and grabbed his hand, moving him in a rhythm that had nothing to do with the song. It was very basic, but he laughed and accompanied her anyway.

He would have liked to see that scene from the outside. Elsa in a oversized white shirt and old gray sweatpants, face flushed and hair in crooked, messy pigtails. And the both of them, dancing, playing imaginary instruments and singing so loudly all the neighbors could probably hear, because no one was looking and they were truly terrible at it.

Jack didn't want to leave, didn't want time to pass. He feared he would someday forget how happy and carefree Elsa looked, and how well joy complimented her, and that was the precise moment he admitted to himself he might be a little bit in love with her.

It didn't catch him by surprise. Of course daydreaming about kissing and waking up beside your best friend wasn't the most platonic thing ever. The nature of his feelings for her should have been obvious to him, and now he understood it was; he just pretended it wasn't. He wondered how exactly he could have lied to himself or avoided this for so long. Without realizing, he'd stopped dancing and Elsa looked at him, puzzled.

"What's wrong?" She frowned, and he mentally cursed himself, looking for an excuse at the same time.

"Hm, I'm... Tired. I should go home." He mumbled, and Elsa gave him the I-can't-believe-you-are-serious-right-now-Jackson-Overland look. It was very effective most of the time, but right now he had a weight on his chest, and an uncontrollable need to go to his room and mope over his own incapacity to stop this from happening.

Elsa scrutinized him for a moment, then headed over to her laptop, which was over her bed, and muted the music. Then she turned to him and crossed her arms.

"You're not leaving this room until you tell me what the fuck is going on. I hope you know that." She informed him, and fear stroked him. Elsa had her serious expression on, and she was a woman to be feared in such times.

"It's a, huh, secret." He winced at how weak his voice sounded and cleared his throat, then averted his eyes.

Therefore, he missed the concern on Elsa's face.

"Is it your parents? Or you? Are you sick or something?" She got closer, and Jack blushed and cursed himself again.

"No, Elsa, listen, it's really stupid. I just have to go home and think about it and, eventually, everything will be back to normal." His voice sounded unsure and realized he'd been trying to convince himself. He took a few steps back.

Elsa ignored him.

"If it's stupid, why can't I know?" Elsa crossed her arms and raised one eyebrow, triumphantly, and any coherent words left jack's mind. He couldn't think of anything to say.

"Because... It concerns... You?" His mouth said stupidly, and he really, really wanted to die. Or at least to run away to some obscure, inhabited part of the world so he could never interact with humans again, because he clearly wasn't able to do it without fucking up.

Elsa, on the other hand, was joyous with that piece of information. She sit on her bed, a small grin on her lips, and did something on her laptop. Then she motioned for him to sit beside her, and he did.

"Write it out." She said simply, and gave him the laptop. It was opened in a word processor.

He stared at the screen for a long time. He tried to imagine what it'd feel like, to type the words and see her horrified expression... But she wouldn't let go, and there must be a way to diminish the impact.

Well, there was a more eloquent way to tell her.

He opened YouTube and did a search, and within seconds 'Can't Help Falling In Love' was playing. He put the laptop aside.

While the piano intro started, he heard his own heart thumping. Elsa looked at the laptop with a slight frown, focused. Jack forced himself to watch as her expression changed from concentrated to confused, and from shocked to enlightened. She licked her lips, and by the time her gaze went back to him, she was glowing. Her eyes were somewhat watery, and he panicked.

"Sorry." It came out in a whisper, and he averted his eyes.

He heard her moving on the bed. "Jack?" She called softly, in a low voice, and he looked up. She was close now — too close.

And she was smiling.

Elsa didn't say anything else. She just leaned in and kissed him, and he was so shocked he forgot to kiss her back. She drew back, confused.

"Sorry! Sorry... Can we do that again, please? I'll do it right, this time." He murmured weakly, and she nodded, smiling a little.

They kissed again, but now Jack forced himself to calm the fuck down and kiss the girl back. And they kissed and kissed and kissed... The song stopped at some point, but neither of them minded.

"This was probably a bad time for kissing." She murmured at some point.

"Hm? Why?"

"I think I have the flu." She confessed, and he chuckled.

"And you only tell me this now? Damn it, woman, what am I going to do with you?" He said softly, drawing back and pulling her so that her head was resting on his shoulder.

"Seriously, that's why my singing was so bad. My voice is not like that." She sniffed, and Jack laughed out loud.

"Hate to break it to you, darling, but you suck at singing. Sick or not."

"I do not".

"You do."

"Do not."

"You do."

She shut him up by kissing him, and he thought that was not a bad way to stop talking at all.

Three days later, both of them were at Jack's house, who had the bigger television. Elsa opened the Netflix app after setting up the mini mountain of blankets and pillows on the sofa, and Jack brought the bowls, one with ice cream and one with pop corn.

"What are we watching?" Elsa asked without taking her eyes off the screen. Jack thought for a moment.

"We really have to finish Buffy."

"U-huh. Buffy it is." She agreed and sniffed, accommodating herself on the sofa.

They were in the middle of an episode when Tatianna came home from work. She took the scene in with amusement — which died as soon as she saw their snacks.

"Ice cream is bad for sickness. It may worsen it."

"Yeah, but it's good for the soul." Jack ate some pop corn. "And the soul is inside the body, so technically, it's a great food for the sick."

"Shh." Elsa commanded, still looking at the screen. "Hello, Mrs Overland."

"Hi, darling." Tatianna replied softly, then sighed and walked over to the kitchen quickly, shaking her head and murmuring something about teeth and sugar and kids nowadays.

After a while, Elsa snuggled closer to Jack, who instinctively held her back and caressed her hair with his non-pop-corn hand.

Truly, he didn't feel as if much had changed since they started dating. Partly because they both got sick and felt half-dead, so not much happened, and partly because, well, it really hadn't. The main difference was that he knew she loved him back, in the same way and intensity, and he still felt awed just for knowing it. He still felt hesitant to initiate any form ofaffectionate contact, so she was usually the one who did (after an impatient roll of her eyes, of course). He would still get dizzy with ecstasy whenever she kissed his cheek, or held his hand, or let him hold her like this. But mostly, he felt like the luckiest person alive.

I love my best friend. And she loves me back. He repeated in his mind sometimes, trying to fully absorb the words. They always reminded him of the internet posts of people who were fortunate enough to marry their best friends, and he always got flushed at the thought. He wasn't crazy — it was way too early; he didn't even know which college they were going to —, but the thought was there, and it made him strangely giddy.

(And years later, when he finally gathered up courage and was struggling to get the words out, she understood and laughed and kissed him. And said fucking finally.

But, well, when he told the story to his kids, much later in the future, he said their mother had agreed to marry him with a simple yes.)

Author's Notes 2.0: Guess who's sick and eating ice cream and listening to Imagine Dragons alone? *throws confetti*

Fun fact: sometimes stories just write themselves. I wish that was true to the fanfics I promised I'd write (I'm so sorry, they're coming, please be patient).

Funnier fact: I wrote this mostly at ungodly hours in the night/morning/? (it's 4 AM). I have a shit-ton of things to do, and I'm here, writing sappy fanfiction. Oh, well. Bringing happiness to the world is never a waste of time or effort.

So I know this is not perfect. It's not the way I wanted it to be, but there's no way to improve this in a satisfactory manner, and I really like it the way it this. I hope you liked it too!

P.S.: Snowman Attack is the equivalent of Frozen in this universe, and you have no idea how much fun I had while writing about it.

P.P.S.: I got the math information from [www . math . uri . edu / ~merino / spring06 / mth562 / ShortHistoryComplexNumbers2006 . pdf ] (no spaces, of course).