How to handle this drama

So a little background on the situation... my hubby and I lost our girls almost 3 years ago. We have been fighting to get them back ever since. Hubby's sister has done nothing but cause problems the whole time. She hates me because my mom called cps on them. (Not my fault) well now that we are ttc she has become an even bigger bit and said she is ganja have our new baby taken away. It's killing my hubby that his family is so messed up now. How or what can I do to help him. I've always been there for him, but it just doesn't seem to be enough.