Family and money are never an easy thing to deal with. Lesson learned, when it comes to money being given or loaned, put things in writing as to expectations of gift or loan and how to repay. It saves a lot of headaches down the road and each of you know what is expected.

Definitely, you and your husband should speak privately with your MIL to find out what she wants and expects. As far as your SIL being involved, could she possibly have power of attorney over her mother's business affairs? If not, then she should keep her nose out of things and I wouldn't give her the time of day.

Please don't act too quickly before getting all the pertinent information from your MIL. Maybe she is misinformed about your life situation and thinks you are in a better way than you are. Lack of communication can cause all kinds of problems.

I hope things work out for you!

Hugssssssss
Jean