应该是及其特殊的案件

http://travel.state.gov/content/adoptionsabroad/en/adoption-process/who-can-adopt/adopting-a-relative-for-incoming-cases.html

Foreign Domestic Adoption

For a child relative who does not fit into one of the above categories, it may be possible for an adoptive parent to file a Form I-130, Petition for Alien Relative, with USCIS for a foreign-born adopted child. This process requires the petitioner to show that a final adoption has been completed before the child’s 16th birthday (or 18th birthday for qualifying siblings), and that the child has been in the legal custody of and shared residency with at least one adoptive parent for at least two years before the petition is filed. The qualifying two years must generally be satisfied outside the United States in the case of a child deemed habitually resident in a Convention country.