Would you do this?

My mother always wants me to "yell" at people for her. Yell at my sister for not doing something, yell at HER mother for not calling, yell at HER husband for being an ass. I just don't get it! After, I don't even know how many years of this, I told her I won't do it any more. I told her I would never ask my future kids to yell at her or anyone to get involved in a fight I was having. She wants me to stand up for her and show her I'm on her side but it is exhausting. It's also unhealthy. I am so over it!