If you have to pay your parents back then it is still a loan.
You had indicated earlier a 136K price difference between UIUC and Stony Brook. Even if you were to earn about 10K per year more for the same job by going to UIUC rather than Stony Brook (very unlikely) and even if you did not pay any interest to your parents (and assuming no gift tax implications) it would still take you close to fifteen years to break even.
I believe that borrowing more than what you expect to earn in your first year after graduation is unreasonable.