Presented without comment.
The first note was passed just days after Elsa's isolation had begun.
Of course, Anna was still very confused as to why Elsa wouldn't come out to play with her anymore. Every day she'd come out of her room first thing in the morning- that was another thing, she never remembered having her own room either- and head straight for Elsa's door. Following her traditional greeting of "Do you wanna build a snowman?" (she asked every single day, first thing, just in case, even though she no longer knew why), Anna would sit at the foot of the door and talk on and on and on, about anything and everything. About her books, about sneaking about the castle, about how much she missed her sister. And Elsa would sit there, just inches away, head rested against the door, listening to her beloved sister. Finally, she could stand it no longer. She may have been forbidden from seeing Anna again, but she was not dead, and she absolutely still loved her sister, more than anything. She decided to take matters into her own hands.
She got up at the crack of dawn, knowing full well Anna would be knocking on her door soon. The younger princess had always been an early riser, and if she wanted this to work, she had to be ready.
The moment she heard the knock, followed shortly by Anna's voice, she froze (pun intended). Elsa could not move, no matter how hard she tried. The note trembled in her hands, crumpled by the vice grip with which she held it. She was on her knees, her head against both the floor and the door, curled up in a ball with the note clutched to her heart. As the icy princess lay broken and crying, her sister remained rested against the other side of the door, going on about her adventure of the previous night, completely oblivious.
Elsa felt the courage rise in her throat just as Anna's voice started to slow. She thrust the tiny note beneath the door, but the moment the piece of paper left her hands, she heard the soft steps of Anna skipping away down the hall.
It was swept up by the maid a few hours later. Anna never saw it.
I miss you so much.
It took several months for Elsa to allow herself this one tiny act of defiance once more. If she'd been caught the first time, her parents would surely have sent her away from the castle. Again she woke early, anticipating Anna's arrival. This time, she was ready. The moment she heard the knock on her door and her sister's voice, she slid the note under the door.
She'd spent hours composing it, trying to find exactly what she needed to say in as few words as possible. In the end, she wasn't satisfied, but it got the point across. It was to be a response. An answer to her Anna's constant "do you wanna build a snowman?"
Anna finished her question, only to immediately notice the piece of paper at her feet. She picked it up, read it, made a disappointed squeak-grunt, and turned on her heel, trudging off with an air of defeat.
I want to, so bad. But I can't.
The notes would come very rarely. For the most part, Elsa was content to listen to Anna talk about her life, and Anna was happy knowing Elsa was listening. Every few months or so, Elsa would slip another note under her door for Anna. Sometimes they were simple little things, words of encouragement, observations of the weather, or perhaps asking about something Anna hadn't brought up in a while. It was difficult and frustrating to carry on a conversation like this, but it was all Elsa could do. Anna roamed the halls, making friends with the portraits and the servants and playing like a young princess should, but Elsa was trapped, a prisoner in her own home, in her own heart, unable to leave not for fear of punishment, but for fear of destroying that which she loved most.
Once, shortly after Anna's twelfth birthday, the younger princess asked Elsa the question she'd been dreading for years.
"Why don't you come out?"
She'd never been given a proper answer; it was only spoken of in hushed tones, or maybe a "you'll understand when you're older."
She was tired of not knowing. So she asked. And she refused to let it go.
Each day Anna would knock on Elsa's door, and instead of asking "Do you wanna build a snowman?", she would ask "Why don't you come out?"
And each day, Elsa would sit against the door, crying in frustration, in despair, wishing she could answer.
And each day, Anna would wait in silence for a few moments, before walking away in disappointment.
Finally, on the fifteenth consecutive day of knocking and asking and walking away sadly, the note came.
It was customary, within their strange little ritual, for Anna to knock three times, ask her question, and then wait a moment for the note she always hoped would come. This time, however, Elsa didn't even wait until the third knock to give Anna her answer.
Anna picked up the paper, examined it, flipped it over, tore it to bits, and stomped off in anger.
She didn't visit again for two more weeks. Despite her isolation, it was the loneliest period of Elsa's entire life.
I'm scared of hurting you
The day word of their parents' demise reached the castle, Anna was beside herself with grief. She was truly alone, for the first time in her life. She couldn't even remember what Elsa looked like anymore- couldn't imagine how different she'd be than those hazy memories she had. But still, Elsa was all she had left, so she got up that morning, well aware of how empty the castle felt with those two less presences. She knocked on Elsa's door, asking with a sob, "do you wanna build a snowman?"
The next morning, the note was there when she arrived. There was no need to hide it; there was nobody to stop her from coming out anymore. Nobody but herself.
Anna picked up the note, slumped onto the floor, and wept.
I'm so sorry Anna. I miss them too.
The very last note was sent under very different circumstances.
It was after Elsa's coronation, and despite the fact that the gates had opened, despite the fact that she'd come to terms with her powers, despite the fact that she'd finally reunited with her sister, Elsa still locked herself in her room from time to time. She'd spent thirteen years living in fear and isolation; it wasn't something she was capable of getting over in just a few hours.
Anna had grown up a great deal, though. She'd seen her sister again, she'd finally found out why Elsa refused to come out of her room, and she'd rejected Elsa's concern entirely. Elsa may have been scared of hurting Anna, but some people were worth freezing for.
Anna knocked on the door, but said nothing. She knew Elsa would be just on the other side of it, waiting to listen, out of habit, out of tradition, out of love. She wasn't sure.
She slid the note into the room, hoping the message would be clear.
Elsa burst forth from the room, startling Anna a bit, wrapping the princess up in her arms as tight as she could. They both laughed and smiled through the tears, feeling truly whole for the first time in forever.
After that, no more notes were passed beneath the doors of the castle. Why pass a note to your sister when you have the same bedroom?
I love you Elsa