2. Who is eligible to file an orphan petition?
A married U.S. citizen and his spouse (no special age required) may file a petition for adoption of an orphan. The spouse does not need to be a U.S. citizen. However, the spouse must legally live in the United States. Also, an unmarried U.S. citizen of at least 25 years of age may file an orphan petition.
但好像還是眾說紛紜沒有定論,有簽H4成功的也有簽B2成功的。好像很難下定論,取決於簽證官的心情吧