You must actually be a citizen to petition for your mother. Passing the naturalization test or being recommended for approval to file for your mother. Once you have actually become a United States citizen, you can petition for your mother. The process will take approximately 6 to 8 months. Your mother must be careful if she timed this trip with your naturalization in order to circumvent the normal immigration process.
Once your mother becomes a lawful permanent resident, she could petition for your sister. Your sister's daughter can derive immigration benefits of under 21 at the time a visa becomes available. The process will take at about 8 years due to visa availability.
You can read more about family immigration at http://myattorneyusa.com/family-immigration.
Answered on May 20th, 2016 at 3:43 PM