Baby Tooth fluttered around Tooth Palace excitedly. Jack Frost was coming to visit her! Sure, he came pretty much every week, and he was technically coming to see his memories again, but that didn't dim her excitement in the slightest. It never did.

Suddenly hearing commotion in another part of the Palace, she sped in that direction, only to find the disturbance was not made by the frost spirit, but by a small girl with shoulder length brown hair and big brown eyes. She was attempting to attract the mini-faries attention, and Baby Tooth rolled her eyes. Couldn't the girl see they were busy? She darted down to the girl and began tugging on the hem of her well-worn dress, trying to make her leave the others alone.

"Hello, little fairy. Can you tell me where the Tooth Fairy is? I've heard she can help me with something..." The girl's voice was soft, and oddly familiar. Baby Tooth moved to hover in front of the girl's face for a moment. Where had she seen that expression? She'd never seen this girl before, but she knew those eyes! And the girl's nose looked just like... she didn't know.

She should take her to Tooth; she'd know who this girl was. So Baby Tooth flitted away, stopping to allow the girl to catch up now and then.

It had been a good day for Jack Frost. He'd brought winter up the east coast, played with Jamie and his friends, and annoyed the Easter Kangaroo into throwing a boomerang at him. Jack froze it to his paw afterwards.

As he swooped into Tooth Palace, he momentarily wondered where Baby Tooth was. But no matter, he wanted to see his memories again.

He spotted Tooth hovering near the North American spire. She seemed to be talking to someone, but Jack couldn't see who. He drifted down to stand on the walkway on the other side of the tower.

"...You sure you want to see your memories? The last ones are always so sad, sometimes, it's better not to know." Tooth sounded rather worried, and Jack knew she was saying this because her own memories were tragic, as all spirit's memories were.

"No, I need to see this. I need to remember. The moon, he said, he said to seek out my memories, I need to know..."

Jack knew that voice.

"Well, if Manny said so, I suppose you do need them. Here. Just press on the diamond and they will start." Jack slowly walked around until he could see the owner of the voice. He nearly had a heart attack. His sister. That was his sister!

She was sitting cross-legged on the floor, staring intently at a memory box he knew must be her own, and Jack realized with a start that she was watching her memories.

He was so focused on his sister that he didn't notice Tooth turn around.

"Jack! You can't be here now! That's the bringer of Spring! You'll kill her!" She shrieked, and Jack tore his eyes away from the girl, amused.

"The Spirit of Spring?" He asked, hardly believing his ears. His sister was the Spirit of Spring! "And why would I kill her?"

Tooth sputtered. "She's Spring! You're Winter, wouldn't you.. freeze her or something? I don't know!" Jack laughed.

"Have I ever frozen one of you guys? I have better control of my powers than that, besides, I would never dream of harming her."

"You've frozen Bunny. And she melts your work, right? Wouldn't you be mad at her for that?" She wondered.

"I froze Bunny on purpose, and... I guess I was annoyed at her, until now... Now I know who she is." Jack answered, thoroughly confusing Tooth.

"What do you mean?"

"I could never be mad at my sister. My human sister, who I haven't seen in three hundred years... I don't know how she became a seasonal spirit, I'm just happy that I can see her again. Um, how long will she be in that trance?"

"Your sister... So that's why she seems so familiar! She should snap out of it soon, she... didn't live very long." Tooth said sadly.

"What!? But I died to protect her! I wanted her to live a long happy life, not... Wait. What year did she... become a spirit, exactly?" Jack asked, furrowing his brows.

"I don't know, Jack. You'll have to ask her," Tooth said, gesturing to the girl. Then her eyes widened. "You DIED!?"

"Oh, uh... Yes?" Jack flashed her a sheepish grin. "May have fallen into a frozen pond while skating... But I'm okay now!"

Before Tooth could reply, Mary's eyes flew open.

"I had a brother! I had a brother... He saved me, Toothiana, I-" She stopped, seeing the winter spirit.

Jack stepped forward with a smirk, arms crossed, and sternly voiced words he knew by heart. He'd said the same thing many times to this same girl, long ago. "Mary Katherine Overland Burgess, I want to know what happened right now, or I'll, um... I... I won't play hopscotch with you tomorrow!"

For a moment, Mary just stared, mouth open, as her brother laughed.

"If you leave your mouth open like that, dear sister, you'll get flies in it," said Jack, eyes twinkling. "I've missed you."

Mary sprang into motion. "Jack!" She ran toward him and he picked her up, twirling her around just as he always did. "But, oh, Jack! How are you- I missed you too, Jack! But you died, how are you here, Jack? Are you a ghost?"

"Whoa, whoa, slow down, little lady! I'm not a ghost, the Moon brought me back. If I was a ghost I couldn't do this," Jack said, poking his sister's nose. She gasped.

"Jackson Overland Burgess! You know I don't like it when you do that! Why are your hands so cold, anyway?" Jack hesitated slightly.

"Well... Ever heard the expression, 'Jack Frost nipping at your nose?' That's me. I'm Jack Frost. And I just nipped your nose." He grinned.

Then he looked into her eyes, serious now. "Now, Mary, tell me why you're a spirit now, and when that happened, and I'll go pester Father Time until he lets me go back in time to make it better, okay?"

"Jack, I died... Because you weren't there to make me happy. In the spring. I didn't eat, or sleep, or anything after you fell through..." She said in a small voice. "And the moon brought me back so I could be with you again. But why'd he wait this long, Jack, I was so alone!"

Jack held her close. "I was alone too, Mary. For three hundred years... I didn't remember anything before waking up in the lake, and seeing the moon." And then Jack smiled. His sister didn't need to be sad or alone anymore. "But now, I'm a Guardian, and kids, kids believe in me! I made them believe, Mary!" He jumped up and did cartwheels around her.

She giggled at his antics, her face lighting up with glee. "Oh, I almost forgot to tell you! I have a new name, too! I'm Mary Springs!" Jack grinned. Then he remembered, he'd promised Jamie he'd visit tonight.

"Hey, Mary, do you want to meet my first believer? I bet I can get him to believe in you!" Mary's eyes widened.

"Really? Can we, can we?" She hopped up and down, eyes sparkling.

"Yep! Jamie believes in everything! Here, I'll give you a piggy-back!" He stooped and let her climb onto his back, glancing at Tooth, who had watched the exchange with a smile. "Hold on tight!" he said, leaping into the air.

His sister squealed when she realized they'd left the ground, and clung tighter. "Jack! You didn't tell me you could fly!" She screamed over the wind.