Frostbound - Zirian Chronicles, #101

An unbearably cold winter. A broken Door. Hundreds of tribesmen missing, scattered across the universe. Her community is broken, dying, and there's nothing Magret can do about it. And as if all that weren't enough, Magret then discovers that with her birthday drawing near, she alone must make a decision: she must choose between her mother's tribe and her father's--both of whom were exiled the same day she was born.
Accompanied by an elder from the community she grew up in, she travels miles north to meet with the leader of the Kalt tribe, and discovers that sometimes the simplest choice is not the right choice. This short story is set parallel to Singular Cipher, book 4 of the Zirian Chronicles.