When can my Us citizen son apply for us as a family for green card. he is 16?

A U. S. citizen child must reach the age of 21 before being able to sponsor parents and siblings. Prior to the change of law in 1976, babies could petition for parents and siblings, but Congress became alarmed and raised the age limit to its present 21. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.