Why does my past deportation effect my visa application if I was a minor at the time?

Consular officers are very wary of giving nonimmigrant visas requiring nonimmigrant intent like F-1 student visas to those who have already been deported since the applicants have already shown an immigrant intent. Your sister could try again in the future for the student visa and perhaps meet a more sympathetic consular officer. I suggest applying again in six months and perhaps giving in a letter explaining what happened in the past and why it would not happen in the future and why she wants to study in the US as opposed to any other country. 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.