Wow, Linda! That seems a tad extreme. Do you have any idea why MIL didn't just address this with your SIL?
Pardon the diversion from the topic, but I haven't read any updates of late about your sister. I sure hope she's doing okay. You are still very much in my thoughts and prayers.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher