How can I help protect my mum from my dad’s lifelong verbal abuse?

My dad is 72 my mum. is 68.

Ever since I was born he has always verbally abused my mum.

Me and my sisters stand up to our dad when he treats her like this.

She won't leave him, when I said bad things about him to her she starts hitting me.

He's ruined birthdays, family outings, I no longer have extended family because of him.

I can't take his crap anymore.

He said to me "you'll be sad when I'm gone" I replied "I can't wait when you are and I'm not going to your funeral." He got really angry at me after that.

I really don't know what to do about my dad's behaviour.

He grew up in then Yugoslavia with an abusive father so. I see the pattern.

It's affecting me and my mum's life.

I don't live with them but I don't know what to do about her safety.

How can I help protect my mum from my dad’s lifelong verbal abuse?
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