Filing an immigrant visa petition does not take long: it can be prepared in a day. If it is done right, it will be approved in about 1 year. Then, the real wait begins. Brothers and sisters of U.S. citizens receive 65000 visas each year; the number of people who file immigrant petitions for their brothers and sisters is much greater. So, after your brother's petition for you was approved, you got a place in the line behind all those who had their petitions filed earlier then you. Because a disproportionate majority of the petitions are filed for citizens of China, India, Mexico, and Philippines, these countries have their separate cues. Right now, the Department of State is processing immigrant petitions in this category that were filed in January-February 2001 (June 1996 for Mexico, February 1989 - for Philippines). So, if you are not a citizen of Mexico or Philippines, you can expect to wait for your visa for another 8 - 8.5 years (16 years if you are a Mexican, 23 years if you are a citizen of the Philippines). It is not clear what you mean by your "whole family": when your wait is over, and you go to the U.S. Consulate and receive your immigrant visa , your wife and unmarried children under the age of 21 can immigrate with you, but your siblings (i.e., brothers and sisters) do not get any immigration benefits from approval of the petition your U.S. citizen brother filed for you.
Answered on Aug 08th, 2012 at 7:28 PM