A/N: Rise of the Guardians belongs to Dreamworks LLC. All use of characters here is strictly for entertainment purposes and not for monetary gain. Apologies for any OOC or typos/grammatical errors missed. I lack a beta. Some liberties taken with the abilities of the Man in the Moon.

It started when Jack returned to the Northern Hemisphere. Perhaps a few residents of Burgess found their windows patterned with frost in the morning, but the game he played just with Jamie. His first morning back, he frosted one window pane and left a "hello again Jamie!" written there.

After several weeks, Jack has even learned to write backwards so the warmth of the bedroom doesn't melt the ice so quickly; he can write from the outside. In the pane next to the one Jack uses, Jamie tapes a notecard with his response to the frame, writing facing outward. From these messages, Jack learns Jamie's birthday is in November - just two weeks away - that school isn't very fun, that he and the other kids are really close. Cupcake and Monty, for example, started hanging out. They both like fantasy and she protects him from bullies while he helps her with math. Jamie learns Jack is adapting well to what Santa Clause and the Toothfairy, Sandman and the Easter Bunny are teaching him about being a Guardian.

Jack sees Jamie outside the messages as well. Walking home from school with his friends, playing during recess, adventuring to Jack's pond on the weekends to explore. Jack watches over them, showing himself only every once in a while. It's not that he's too busy - it's still a little early for snow days and hijacking sleds. He's not sure what it is, but the apprehension is there. He's aware that while they can see him and touch him like he's one of them, he's still not. He's still timeless, ageless Jack rescued dead from the pond outside of town by the Man in the Moon three hundred years before. So small a change to be believed in, to be seen and part of the world of these kids. Huge, for him, to be noticed, to not be invisible and wandering silently in the shadows, unheard when speaking and unnoticed when throwing snowballs. But it's a double-edged sword. The bond is personal now - not just a distant appreciation for these laughing, playful, bright-eyed kids, but a real bond. Between two people - or rather, a kid and and a magic boy protecting them with snow and ice and a heaping dose of fun. And he's worried about what it means for him when they grow up. When they stop being able to see. When they grow old and wither and pass away.

Two weeks before his birthday, Jamie leaves this message in his window: "Will you have time to see us this winter? The guys all miss you. I do too. And my uncle did some research on our town, on our ancestors. There's a legend about the pond he found. When I see you, I'll tell you! See you soon! Jamie."

Jack taps the glass gently with the hook of his staff and the ice curls and fans from it until the pane beside the note is covered in frost. With his finger, he writes backwards, "Of course I will. I miss you all too. This is my Home. I'd like to hear the legend. See you soon! JF."

Jack leaves then, and busies himself in Scandinavia while Sandman spins his dreams, Russia afterward, a short blast on the winter wind to Alaska and Canada, gilding everything in silver-white and watching eagerly for the surprise and awkward recoveries of people noticing a patch of ice here, a light snow there, a surge of winter wind that makes them shiver and flee indoors. After dawn, he spends the day practicing conjuring ice birds, inspired a little by Baby Tooth, as helpers. As a Guardian, he's stronger now - much stronger - now that children believe in him, know his name, blame him for nipped noses turned rosy red upon inspection in the mirror. But they smile and cherish the idea, and his abilities grow. He can protect even more of them if his reach is wider, longer. So he tries with the birds. So far, they're not to him what Baby Tooth and the other fairies are to Toothiana. They're not individual or sentient, but they can go from here to there and back again with small tasks. They can sing and call clouds in for a good snow, graze buildings and fences and cars and anything else with their wingtips and leave a healthy frost in their wake. He can make them a little bigger now, too, but they don't think on their own. When night falls he decides to ask Tooth about it and leaves the Pond to go see Jamie's response.

There isn't one. Jack smiles, taking it to mean the boy was serious about telling him in person. So much for putting a little distance between them. He sticks to Burgess that night, deciding to walk with him to school the next day so he can hear the story about his Pond.

Long after it's time for school, Jamie is nowhere to be found except in his bed, at home, his mother pacing his bedroom frantically and speaking hurriedly on the phone. Through the glass, Jack watches her, confused. Jamie doesn't look sick - he's just lying in bed, sleeping.

"...watch Sophie," Jamie's mother is saying, "No, I don't think that's necessary. I don't know how long I'll be, Danielle, I'm sorry. I know you were looking forward to having Founder's Day off from school, but it's just until I get back from the hospital. Can you make it?"

Looking between Jamie and his mother, Jack is very confused. "Why does he need to go to the hospital? He doesn't look any different at all. He's not even awake, how does she know?" He's seen kids get sick before, and mother's aren't this frantic about it usually. And they don't usually have to make emergency hospital visits because a child is sleeping peacefully in bed.

Creeping into the room while Jamie's mother negotiates pay with the babysitter, Jack steals over and shakes Jamie by the shoulders. "Come on, buddy, wake up. Your mom's freaking out." Earning no response - not even a grumble - Jack shakes him a little harder. "Jamie? You don't really need to go to the hospital, right...?"

The boy is eerily still. Jack takes a step backward, really confused now, and lets Jamie's mother - who has hung up the phone - bend down and pick up her son and walk him out the bedroom door. Jack follows without looking back, but doesn't make it through the door.

"Jack...?"

Turning, Jack faces Jamie, still lying in bed. His eyes are open now, but he looks strange, washed out somehow. "Jamie?" Jack drifts over to his bedside, trying to understand what he's just seen. Trying to understand what he sees now: Jamie's hands rest on the edge of his coverlet, and through them Jack can see the blanket's pattern.

"Do you see me?"

Jack's heart breaks a little. It wasn't so long ago he was asking of Jamie something similar. "Buddy, I've been seeing you this whole time."

Jamie shakes his head. "No, I've been awake this whole time! You thought I was asleep, too. I don't understand. I'm awake!"

Jack sits beside him and puts a hand on his head, hoping it doesn't fall through his face. It rests gently on top of Jamie's hair. Transparent, yes. Insubstantial, not so much. Considerably relieved, Jack grins.

"It sounds like you had the day off today anyway," Jack tells him.

Shaking his head, Jamie withdraws from Jack's hand. "I feel really weird, Jack. Like something really important is missing."

Jack is getting the feeling Jamie didn't see his mother carrying him out of the room. Lacking an explanation for the phenomenon, Jack smiles at him. "I know. We're going to go find out what it is. You and me. Sound like fun?"

Jamie nods. To keep up the illusion, Jack holds out his hand. "Remember how to fly?"

Instead of by Sleigh, Jack arrives at the Toothfairy Palace by Winter Wind, Jamie's hand tight in his own. As usual, the little fairies are bustling and zipping about, bringing teeth in and taking quarters out. One fairy breaks off from the incoming fairies and circle's jack's head, chirping happily. Landing, Jack releases Jamie on a landing and catches Baby Tooth in his hands. "How ya been, Baby Tooth? Getting lots of teeth?"

She chirps an emphatic, excited response, and holds out three for Jack to see. He grins. "Good job," he says. "Is Tooth out in the field, too?"

Baby Tooth puts the teeth away in a little satchel and shakes her head. Gesturing for them to follow, she flutters off around the Palace. Exchanging looks, Jack takes Jamie's hand again and summons the Wind.

Baby Tooth takes them to the Hub, a gazebo-like place where Toothiana gives her fairies instructions on where to go next. She squeaks in surprise when she sees Jack and Jamie, still transparent. The support pillars and lattice around the gazebo are visible through him.

"Jack, what's going on?"

Jack smiles. "You remember Jamie, right?"

"Of course I do." She flutters down to hug the boy and looks back up at Jack. "Something's wrong, though, isn't it?"

"Yeah," Jack said. "Jamie and I are trying to find out what."

"What do you know so far?"

Leaning on his staff, Jack, bites his lip. "That Jamie thought he was awake this morning, but he wasn't. His mother took him to the hospital, and I was going to follow, but he called after me." He slides down the staff to kneel at their height. "Jamie was still there, but he was like this. Have you ever seen anything like it?"

"No, I don't think I have," Toothiana says softly, stroking Jamie's hair gently. "Do you remember anything strange, Jamie?"

The boy nods. "There was music in my dream last night. The same song over and over again. It sounded like a flute was playing it, and other kids were singing it. I really wanted to join in, but it stopped suddenly and I woke up to Abby jumping on me."

"Abby?" Tooth asks.

"The Greyhound," Jack says with a wicked smile, remembering how fond Greyhounds are of rabbits.

Tooth nods. "Music. Music... Oh, I know! Let's check your box!" Fluttering up, she takes Jamie by the hand and leads him toward one of the shining towers, Jack following on the Wind close behind.

Jamie's box is doing something very strange indeed. The flute song he was hearing is playing from it, Ring Around the Rosy, over and over again. Toothiana frowns. "That's very unusual."

Nearby, Jack pulls another box from a shelf a few feet away. "His isn't the only one," he says, letting them both listen. The same instrument, the same tune. They are even synchronized. Toothiana's face drops into a small panic and she scours the shelves, finding several more before putting them all back and dropping down to Jack and Jamie.

"We need to talk to North. He'll know what to do."

The Yetis are still wary of Jack out of habit, but Toothiana has been a Guardian much longer and they trust her judgment easily - for Yetis. And she absolutely will not abandon Jamie, so in he goes.

"Slow down, I want to see this!" Jamie complains, pulled along by Jack. The Guardian looks over his shoulder sympathetically.

"That's what I said my first time here, too. I'd tried for years to break in. Sorry Jamie, but you're not even supposed to be here. Oh, and no telling the others, okay? This is just between you and me."

Toothiana steers them off into North's workshop and the door closes abruptly behind them.

Jamie's eyes widen. "Santa Clause!"

North laughs. "Of course. Have cookie," he says, offering a plateful to the transparent boy. When he realizes he can eat them, they go quickly. While he eats, Jack and Toothiana explain what they know. North paces and strokes his beard.

"The Globe is in good order. You say you heard other children singing?"

Jamie nods.

"Could be..." North hums to himself, pacing and thinking. Suddenly, he turns to Jack and Tooth. "You two! Go scout for information, see if you can learn if other kids have gone missing."

"Kids always go missing," Toothiana says softly.

"You mean, a lot of kids? All at once?" Jack asks.

"Yes! Go, and check back in here around nightfall. I'll look after this one and summon the others."

"Others?" Jamie asks. "You mean the Easter Bunny and the Sandman?"

"The very same," North grins.

"Come on Jack," Toothiana says.

Pausing to ruffle Jamie's hair, Jack looks at North. "Take care of him!"

"You know I will!"