DD here is showing definite signs of being affected...even our 'Lil Elder Cat is with different (uggh) behavior.
There are so many different pieces of advice for that situation, DBell. "We" switched back and forth, trying to see what worked, but I never could stand ignoring it, like Happy Pants does. He and siblings were taught that emotion is bad and should be had by oneself...go in the other room when you are sad, glad, or bad.
I do not wish this for my children and I want them to feel safe when they have emotions, even like you describe with your daughter.
I'm sorry there's no real piece of proactive advice, rather a passive message, but I'm thinking.
I'm taking a psychology class right now and the newer trains of thought are NOT to ignore the feelings of any age child, but to assist them-somehow-in working through.
I have a cousin who, when his DD has that behavior, he wraps her in a bear hug and doesn't say much until she finishes. He said, it's no time to argue or try to use ration but he can't stand the agony that is so real on her face and wants to do something for her...but he won't give in, either. So in order to show her she is not alone and her feelings are in some way valid, he does that.
When she is calm, he tries again and finds a different way about the same topic or problem.
She does not necessarily get her way, unless it is what he needs or the situation at hand needs, but they also talk about it after it's all done.
In my class they call this "emotion coaching" and I really like the idea...I've done it with our daughter and Happy Pants (STBX) would get annoyed. Like I said, I want her to grow up unafraid of feelings. Otherwise, how do they learn that feelings also will go by?
Bravo for trying not to fight in front of your daughter, it is commendable but not always easy. We work at if we have to speak, too.