The advise that is counter-intuitive works. It is now common sense to me. Stand up to irresponsible behavior with boundaries. Point out the two choices (irresponsible and responsible) and what actions you will take for each choice. Clearly state how the person you are talking to needs to behave in order to show responsible behavior.
One step away:
"When you yell at your sister, I feel my energy draining. If you continue to yell, I will not have enough energy to take you to the birthday party tonight, If you calmly discuss your concerns with your sister, I will take you to the party tonight."
My kids know this is no bluff and stop yelling.
"What is best for my kids is best for me" Amor Fati Link to quotes: https://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2879712