If an unwed Mother abandons her daughter to the custody of the unwed Father, Is the Father now have Primary Custody?

If I understand your question, the short answer is "yes."  Nevada law for unmarried parents specifically provides that the father of an out-of-wedlock child whose mother abandons the child has presumptive primary custody.  And yes, you should "do something about it" -- file a paternity action, and establish paternity (if you are not already on the birth certificate), your primary custody, and a support order.  See: http://willicklawgroup.com/paternity/ http://willicklawgroup.com/child-custody-and-visitation/ http://willicklawgroup.com/child-support/ Then schedule a consultation with this office or that of some other family law specialist, go over all your facts and circumstances, and any written records, letters, e-mails, etc., that support your story, and arrange to have the appropriate papers filed.