This is a moral dilemma and I just do not know what to do.
My SIL is the sweetest person but she has been having problems with her DP for a long time now. We started off by offering our support and encouraging her to try and make it work but the more we see the more we are uncomfortable with.
We have her DS and her DP picks him up from us. He often says some very rude comments about SIL and has said things that we know SIL would not want people knowing. Because he says them so freely, and openly (we no longer let him in the house and meet him at the door with his DS) we are starting to think that he is unhinged and is thinking of things to say before he comes round.
They have just relocated and are staying with DH's parents while they look for somewhere else. Things have gotton worse and he frequently says things about MIL to DH, it is very disrespectful and DH puts him straight but does not tell SIL as we both feel they have enough problems.
However we have just spent a whole weekend with them and it was a nightmare. We have not told SIL what he has been saying/doing as she would be devestated if she knew he had told us some things he has but I feel like he is using emotional blackmail to control her and she needs to get away from him.
My DH feels we should now tell her some things we have witnessed. I know from my own experience with my sister that she has to be ready by herself to take those steps. I have no doubt that she would believe us,she knows all of this already but wants to try for the sake of DS. Both my husband and I witnessed him pushing DS on the floor abd pinning him down at the weekend and confronted him but worry what happens when no-one else is around.
My worry is that we are making very strong accusations against him and should we step in or butt out.