F2B 是永久居民的成年未婚子女；申请人结婚之后自动作废。若要想完成 F2B 移民，什么时候才可以结婚呢？新泽西移民律师事务所 Lee & Garasia, LLC 在这篇文章里有解释：
[…] if the F2B beneficiary of an I-130 petition marries while the petition is pending (or for that matter, even after visa approval but before immigrating to the United States), the petition will, for all practical purposes, be invalidated. In other words, the individual will no longer be eligible for the visa as an unmarried child, since he or she is now married. It does not matter that the beneficiary married after the I-130 was filed; after the I-130 was approved; or even after the visa is granted. If the person is married before entrance into the United States, he or she technically does[not] qualify for the visa.