Two of Gratillonius' daughters fight. Dahut has drowned but returned as a siren. Nemeta is afar but attacks in her Sending as an eagle owl. Dahut is solid to the touch but also spiritual enough to grasp the right wing of the incorporeal owl and thus to harm the right arm of her distant half-sister.
Dahut is not a ghost but more like a draug, not an unquiet spirit but an unquiet corpse! With direct experience of such uncanny, physical manifestations, it is no surprise that mortals invoke Whichever seems to them to be the most powerful deity. For Gratillonius, this becomes Christ.