This mystery can be found in the northwest of Glowecestrescire, not far from Thieves Warren. As you approach the area, you’ll hear a woman in childbirth. Speak with her to begin the mystery.
Where to Take Ermina on Horseback
After the initial conversation, you’ll need to take the woman (Ermina) on horseback to the ruins on top of the hill to the northeast. Along the way you may be ambushed by wolves, so you’ll need to deal with these by shooting them from horseback or dismounting and taking them out on foot. This is necessary because you need to be anonymous when you reach the ruins before the mystery will progress.
Once you reach the top of the hill and the highest point of the ruins, a cutscene will play during which Eivor assists Ermina in childbirth. At the end of the cutscene, the mystery will complete.