My sister struggled with the same for years (our dad though), and I finally gave her the same advice your sister did for you. Sometimes it's way easier to have a paradigm shift within ourselves instead of expecting it from someone else. Years ago I just decided that my father did the best he knew how to, with the knowledge that he had. Was it good enough? Nope. But that becomes irrelevant when you decide to forgive, move forward and vow to change the cycle with your own (my) children.

Thank you for sharing such a valuable lesson with all of us @jusipassetti!