After escaping from the dungeons of Arendelle, she secludes herself in the Mountains, away from the Kingdom and all the memories she had. During her isolation, she searches for a way to melt the ice and end the winter she caused.
Why don't we know more about our princesses' past? Why do they always seem to be a secret? Twilight Sparkle believes she has just found another secret of theirs. And this one seems to be more about their family.