Etheryn's companion quest.
1. Etheryn seems intent on getting to Castle Hawkstone, seat of the Frost March's hereditary baron. As a princess of the Winter City, she's likely got something important to say during this meeting -- accompanying her would doubtless benefit you as well.
This quest becomes available after saving Etheryn from inside the Wayfort, past the Alraune matron. Depending whether you agree to take her with you or not, she will travel with you and once inside The Frost Hound she can be questioned on the situation; or she will travel to the gates of Castle Hawkstone in futile attempt to get in, where you can find her and offer to join your group.
As of 0.1.9 this is as far as the quest goes.