Why did it happen ?

Uncle Bill would often come home in a drunken state and start by screaming and shouting and banging together a great big pit coal shovel and a massive steel poker at us kids,frightening the living daylights out of us. No one could imagine a grown man even in drink would do the things he did "having fun as he put it, aunt Rose didn't make things any better as she would be screaming at the top of her voice telling him to stop. I was absalutely petrified with nowhere to go and no one to tell. There was on more than one occasion when I wouldn't stop crying he'd pick me up and take me down the yard and lock me in the coalhouse aunt Rose would be begging him not to and him saying " your next" if you don't "shut it". I felt safer in the pitch black dark of the coalhouse  than being anywhere near him. That’s how petrified I was of him.He would eventualy go to bed and aunt Rose would take me out of the coalhouse and things would return to normal.