DD is turning into DS1

[3NAB]

She is 4 and he is 7

She called her dad an idiot, has hit him and both brothers. moved sideways on the stairs so I couldn't get down when carrying something i shouldn't and then pulled a face behind my back

i am sure all normal behaviour but not one I am going to tolerate

I suppose it is inevitable that she is going to copy him!
What's your plan?

no idea

have posted a few threads today about her

It is normal especially if she is copying her older brother. But, as you say, you do need a way to get across to her and her brother that it's not a nice way to behave. Some things can be ignored and some things need pointing out as unpleasant behaviour. Stay calm, breathe deep and talk to her. For starters I'd ask her if she thinks it's a nice thing to do and why would she do it. Let her know that it makes you unhappy and you don't want to be unhappy and you don't want her to be unhappy - that type of thing.

It'll be a long hard slog of your and your DH setting a good example. I'd ignore the face pulling or pull one back depending on the context!

Good luck.