The Immigration Act allows United States citizens or permanent residents to petition for permanent residence for certain qualifying family members.
A parent petitioning for a child can only do so in this category if the child is under 21-years-old and unmarried. (See order of preference for details regarding other immigration categories).
The definition of a child has undergone different interpretations, especially in the area of legitimate and illegitimate children.
A step-child is eligible as long as the parent-child relationship was established when the child was under the age of 18 years.
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