My mom has a really hard time getting along with my sister in law (older brother's wife). I think she tries, but their personalities are so different that they just clash. My brother and his wife have 2 kids together (1 and 9), and the 9 year old my mother can only take in small amounts, and my mother feels the same way. They don't really put limits on her (she can cuss, she has little to no respect for things or people, and has to be entertained 24/7).
She isn't like this with the other 4 grandkids (my 2 and my younger brothers 2), and she gets along well with the other sister in law and my husband. She gets her feelings hurt very easily and this SIL hurts them often. She's non-confrontational so she doesn't say anything then calls me or the other SIL after and vents. I've tried telling her to talk to the brother about it, but she says that he will just take the SIL's side and shut her out. This is not their first rodeo:
A couple of years ago, my mother got her feelings hurt at Christmas because the SIL didn't like what Mom got her, or her daughter (this was before the son was born). So a couple of weeks later, it was the daughter's birthday, and mom didn't show, just sent gifts and didn't call daughter to tell her happy birthday (I admit, this was wrong, and told her such). They didn't speak for almost 2 years, resorting to posting bad things about each other on FB and trying to drag me and the other brother/SIL in the middle. Now everyone is in semi-peaceful land, and here we are again.
I'm trying to prevent World War II, the daughter's 9th birthday is coming up, I'm at my wits' end with ideas of what to tell her, anyone got suggestions?