The Travel Ban that is currently in effect does not apply to close relatives of individuals lawfully in the United States. This includes parents, spouses, children (adults or minors), son-in-law, daughter-in-law, siblings (including half-siblings), grandparents, grandchildren, fiancés, brothers-in-law and sisters-in-law, aunts, uncles, nieces, nephews and cousins.
These family members may have to prove their relationship to you prior to receiving a visa to enter the country.
F-2 Visa Holders - Family members of spouses of students who have an F-2 visa are also allowed into the United States even if those family members come from a country on the Travel Ban list. There had been some confusion as to whether the exemptions for family members just applied to F-1 visa holders, but it applies to both sides of the student-family.
DACA - Some student workers have DACA (Deferred Action for Childhood Arrivals) or have family members who do. For now, DACA is in effect and work authorization is still honored under the program; however, unless Congress Acts, the program will expire in March, 2018.
For updated information on DACA check reliable websites: The Immigrant Legal Resource Center’s DACA Current Status and Options; The National Immigration Project of the National Lawyers’ Guild; and the American Immigration Council.