Parents gonna parent.
It's not right or fair, but it is quite common for a parent to treat their children's concerns as less important, even when the concern is literally the same.
Next time around I'd imitate her approach, yell STOP! I don't like that noise and make that discussion/fight take focus over whatever she was originally trying to discuss.
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When a clown moves into a palace, he doesn't become king, the palace becomes a circus.
"Many of us like to ask ourselves, What would I do if I was alive during slavery? Or the Jim Crow South? Or apartheid? What would I do if my country was committing genocide?' The answer is, you're doing it. Right now." —Former U.S. Airman (Air Force) Aaron Bushnell