Here’s a good reason to become a U.S. citizen – It doesn’t matter if the foreign brother or sister is 16 or 40 or married and have children – that’s okay. But if your U.S. relative only has a green card, the answer is no.
Citizens can sponsor more types of relatives. Both citizens and green card holders can sponsor their husband or wife (same-sex too), and unmarried children of any age. In addition citizens can sponsor their sisters, brothers, parents, married children of any age, and fiancé/es.
Another advantage for citizens is a shorter wait in some categories. There’s no quota for a spouse, unmarried child under 21 or parent – they’re called “immediate relatives.” You still have to go through the paperwork and meet all the visa requirements and that can take at least 6-12 months. Approval is never automatic.
There are quotas and backlogs for other relatives, and for green card relatives. As of March 2015, the backlog in visa numbers for green card spouses and minor children is almost 2 years. You can check the backlogs at the State Department’s monthly Visa Bulletin http://travel.state.gov/content/visas/english/law-and-policy/bulletin.html
You might ask ‘why bother’ sponsoring a sister or brother when the visa backlogs are so long. As of March 2015, it’s over 23 years 
for siblings, from Mexico it’s almost 18 years, and for other countries it’s about 13 years. But I’d suggest you file anyway: I truly believe that some day – not this year, but one of these years – the U.S. Congress is going to pass immigration reform to deal with problems in the U.S. immigration system. In 2013 the U.S. Senate passed a Comprehensive Immigration Reform bill to speed up the process for siblings and married children but would also eliminate visas for siblings and married children over 31 altogether in the future. The bill died and is not law. But it’s likely these relatives won’t always be eligible for family visas, and the sooner the U.S. citizen files, the sooner the green card will be available.
The government filing fee is $420 for the family-based I-130 petition. You can find more information on sibling and other family visas on our website and also on becoming a U.S. citizen .
