I dont know where to start but...
DH does not have a huge family, and it's always been a bit disjointed IMO. However as my parents are both deceased its all the immediate family we have. (I still have aunts, cousins etc but they are miles away - a wedding funeral sort of thing)
Anyway MIL looks after SIL children, and generally spends all day at thier house. She tell us my SIL needs her there.
SIL says MIL just comes round without invitation and sits on the couch all day. She is also cross at FIL who she claims has smacked one of her children, nearly fallen on another when newborn and while a bit merry, and hates her friends children.
DH grandparents also live nearby and since we all had children there has been some animosity between MIL and and them - she seems to find them threatening as they play better with her GC's than she does
Anyway SIL has recently (according to her) been let down by MIL and FIL when she had asked them to babysit. So when FIL asked BIL (his son) to help him shift furniture and BIL did'nt turn up I could'nt help thinkning SIL was behind this.
SIL is due to go back to work in April and has asked MIL to have the kids again, which MIL has always done for free. However MIl went to hosptial recently and has been diagnosed with a physical problem that means she is incapable of caring for small children (no lifting, bending etc). She has told SIL who says she can make other arrangements. But MIL has told DH this means she will no longer be seeing SIL DC's unless they come to her.
GP's have also told BIL not to take his children round thier recently and we dont know why, they have been poorley, but could also be to do with MIL's jealousy.
DH and I live 2 hours away from everyone (they all live withing 2 miles of each other) and just get to hear the individual stories by phone/email, as no one talks about the others in front of one another. So DH and I have become sounding boards I guess.
The upshot is, although I dont agree with MIL and dont enjoy her long-term company, I think she will now be stuck at home everyday staring at 4 walls in an area she hates and getting depressed. GC's will be doing the same just down the road. And SIL will be carrying on regardless as despite what's gone on she can still live her life as she wants.
Should DH and I call crisis talks or see what happens? Bearing in mind MIL and FIL are defensive of thier part in this, ie towards GP's and GP's will not want any bother.