Now, Elsa knew she was going to give Anna the skeleton key for a long time now. It was her way of saying that, even if the door was locked, she would always be welcomed into her bedroom and study. But she wanted to give her something else as well. It was her way of making up for all the other Christmases (although she knew she would have to make it up for the next few years).
And she came up with the silver bracelet. It was beautiful on its own, but she felt it needed something else. So what did she do? She had it engraved so it would say, “I’ll always want to build a snowman.”
"Merry Christmas Anna!" Elsa handed her the two gifts after hugging her tight. She waited until she opened the key before she spoke again. "It’s a skeleton key. It’ll open every door in the palace, including my bedroom and my study. So if it’s locked and you knock and I don’t answer, you can use this to unlock the door, within reason of course."
"I know this hardly makes up for what I did to you, but I hope it’s a start."