Nepotal :: Nepotal (a.) Of or relating to a nephew.
Nepotic :: Nepotic (a.) Of or pertaining to npotism.
Nepotism :: Nepotism (n.) Undue attachment to relations; favoritism shown to members of one's family; bestowal of patronage in consideration of relationship, rather than of merit or of legal claim..
Nepotist :: Nepotist (n.) One who practices nepotism.