He married the girl's mother two years ago, has been with them since the girl was 7. About 5 years now. He has always been crazy about the girl, they are close , but something seems have changed since his son was born 7 months ago. Now he seems negative and sarcastic with her a lot, and kind of pushed her away physically, now that she is a bigger teenager too. She used to sit on his lap and nuzzle etc, but no more. This makes me so sad, this change. I brought it up once with him and the mom there, not the girl. They got very upset and basically told me to butt out. I had suggested that they try to be more positive with her, praise her for what she does right, gently correct what she does wrong, etc. Resist being sarcastic. So I cannot bring it up anymore. Here is my problem. To see my new grandson I have to be around all of them, then I come home very sad about how the girl must feel rejected, and the rivalry of her new brother who BTW she does love. What can I do to not let this tear me up everytime?