&gt;  You could make an arrangement with your family where you explain that you would want to lend the money, but it's not your sole responsibility to pay for it all just because you have the financial means.  You could ask them to set up a repayment system where everyone in the family works together to pay you back, especially those that ask you to pay for her surgery.

This is where getting some appraisals, figuring out LTVs, and getting added to the deeds of property comes into play. Even if the family doesn't want to pay him back, and try to stiff him, he still has a vested interest in property. At some point, they can buy him out through the sale or refinance to pay him back. 

This route may offer one of the best protections to getting your money back in case the fam wants to be shady. It is a little complicated, but can be done. May want to get a real estate attorney involved.