孩子在国内时过继给了当时是绿卡的姨妈。姨妈帮着给孩子办了绿卡。这几年一直跟姨妈在美国生活。现在孩子可以申请公民。那他公民后，可以为国内的亲生父母办移民吗？
-Because the adopted child has obtained the immigrant benefits (green card) through the adoptive relationship, the adopted child cannot sponsor his biological parents' green card anymore.
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