To be a Daughter of the Nile, one must be the female relative (by birth or marriage) of a Shriner and be invited to membership. My mother's a member of Shalman Temple #90 in Dallas. Members are addressed by the honorific 'Princess'. Officers in the organization have names inspired by Arabic princesses, while the presiding officer is the Queen. National officers add the title 'Supreme' to their Princess or Queen title.
A similar organization is the Ladies Oriental Shrine of North America. Both organizations support the Shrine and their philanthopies.
More info:
http://www.daughtersofthenile.com/