My brother-in-law and his wife have Stafford and Signature Student private loans but he has recently had to undergo treatment for a major medical illnesses that, at the least will have him out of state and work for 1-2 months and at the very worst, could be fatal. I could not find specific information about deferments due to illnesses. In light of their extra expenses for treatment along with missed work, what kind of space do they have in repaying their loans (grace period) and are there deferments for major illnesses (severe mono, cancer, etc)? If so, how do they go about applying for those deferments? Thanks!

First of all, as far as deferment goes federal Stafford loans and private loans will be handled very differently. Generally there are more deferment options with federal loans. Here is a link to all of the federal loan deferment options and forms that should be sent directly to the loan lender. http://www.studentloannetwork.com/repayment/deferment.php

For private loan deferment options they will have to speak to their lender directly.

Great, can you point me to who I could talk with on the phone in regard to this statement from one of those web pages?
"The borrower's loan holder can grant forbearance in intervals of up to 12 months at a time and for up to a total of 3 years. In order to enact federal student loan forbearance, it must be applied for through the loan servicer, and payments must still be made until forbearance has been granted."
In other words - who is the loan servicer? Thanks again!

Unless you used a private company that is acting as a third party handler for federal loans, the default lender is Direct Loan Servicing or http://www.dlssonline.com/