DISCLAIMER: Your Steps and Tasks may be different
1) Talk to Eira in Connla she tells you a story about a Siabra family that disagreed with the Siabra policies and moved near Connla and were friends of the Celts in the area. One night a group of Siabra's murdered all but one of the family. Your to find out from the ghosts the name of the one family member that got away
2) Head down the beach S almost to the end and then turn up in to the hills, not far in you'll see a camp (loc=9.9, 6.9). The ghosts only spawn at night, when they do talk to Chief Gaeth and he will tell you that his daughter Kaylee got away and to talk to Marus in Connla as she might know where she is.
3) So back to Connla and talk to Marus (shes's inside the stone building). Marus gives you a note for Kaylee (this is so she'll talk to you) and tells you where she is. Across the river, by the tower with her husband the Celt Iabob.
4) Swim across talk to her and get the Potion of Respite that will release the dead Siabra family from their half-life.
5) Run back to the camp and give the potion to Chief Gaeth and you're done.
***There is only xp and coin given for this quest.