OP here...wow! Lots of responses! Let me try to answer some of the questions:
My husband and I are currently separated, but are working on reconciling. I am not going because 1) I am a teacher and don't have time off until Christmas and 2) my son and I went last month (it was another "budget" trip with old passes and using DVC points -- and we were actually driving down to pick up my brother's dog in FL anyway). My husband doesn't get any time off in the summer, so we used half of our points for our trip and he is using half for his. His sister told them of their trip and he wanted to go with them (really to be with his niece). He is staying in the DVC by himself while the three others are in the Poly.
I thank all of you for your posts and opinions. Probably the post that resonated the most with me was the one by amberjack. If I report this to Medicaid, then it could jeopardize my niece's insurance and could ultimately impact her health (if they don't take her for check ups because of the money). I just couldn't do that.
As far as the actual reporting goes, I am pretty sure that the clause on her bankruptcy doesn't allow for any large purchases (and this would qualify) for a period of time. That money
should be going to the creditors that she stiffed. In addition, I know that you cannot have any assets and have to account for your spending. As far as Medicaid goes, they have to "prove" every month that they don't have the funds for health insurance. Clearly, that is not the case.
My MIL didn't have a will, but she and FIL lived with SIL (gave them free babysitting and paid rent to them every month). SIL didn't pay the rent for over six months and came home one day and told MIL and FIL that they all were being evicted and they had two days to move.

I think that some or all of the money for this Disney trip came from those rent payments paid by MIL that never made it to the landlord.
You all are right. I shouldn't let this bother me. I just have to work a little harder at that.
Thanks for the perspective.
