<p>Were you legally adopted by your sister and BIL? Did your parents terminate their rights through legal documents and your sister and BIL are your legal parents? If so, then it’s all very simple. Regardless of living with your parents or who was supporting you, your legal parents are your sister and BIL just as it would be with any adoptee. And your parents are simply grandparents now. FAFSA is filled out with sister and BIL and any contributions given to you by your legal grandparents are unearned income, just as any grandparents gifts of money and support would be. Not a complicated family tree at all. If your grandparents gave you too much for you to get financial aid, or your legal parents make/have too much, , then you are in the same position as many young people if they can’t or won’t come up with what you need to go to school.</p>
<p>I don’t see any independence in anything you have to say here unless a court took you away from your parents due to abuse , neglect or other such issues, not a willing hand over, AND you were NOT legally adopted by your sister, so they are NOT your legal parents. </p>
<p>If you were legally adopted, then your sister and BIL are your parents. Your parents are your grandparents. Simple as that.</p>