Detect Blood Relation

Colloquially called "Detect Paternity," this spell allows you to divine the nature of the blood relation between two individuals. You touch two creatures, maintaining physical contact with them for the spell's entire casting. You can substitute a small vial containing at least one drop of a creature's fresh or preserved blood in place of touching a creature itself.

Once you complete the casting, you instantly learn the exact nature of the blood relation between the two targets, if any. You do not divine any other details about either target, such as their name or location.

If you break contact with either target (or the vial of their blood) during casting, the spell fails.

The exact origin of this spell has been lost to rumor and legend, though most agree that it almost certainly involved a bard and a noble family. This spell has been responsible for an untold number of duels, murders, divorces, and alimony cheques- use it wisely.