Convincing one's mother to get a divorce

My father has been treating my mother with unnecessary banter and quarrels for about 20 years now. I don't remember a time in my house where we openly laughed. My father does not love my mother, because if he did he'd see the pain he's causing her. My father yells at my mother for no reason and accuses her of such she didn't do. He doesn't trust her as well. He's been causing her all this pain and she's been dealing with it just for her two daughters. I suggested she divorce him. My dad has had a previous wife as well which he divorced. What should I do? Should I convince my mom to get a divorce and be happy?