I have 9 yr old twin DSs and the following behaviour is pretty usual for them:
Screaming, fighting, punching and generally attacking each other for the slightest thing.
Namecalling, shouting and arguing.
Running round (they literally make me feel dizzy) any store we go in, touching and picking things up, sliding down the aisles on their knees
.
Will not go to sleep in evenings as constantly mucking about (have tried separating them but they run between the bedrooms).
Messy eating, slapping lips, slurping (hilarious to them), leaving crumbs in every bloody crevice in the house no matter how hard I try to get them to eat at the table (talking snacks here, meals we eat together obviously).
Have to be told constantly to get ready in the mornings/when we are going out, i.e. upstairs supposed to be getting dressed but I will find them lying on the floor reading or colouring.
Have to supervise their nightly baths as they will cover the floor and all surfaces with water sliding down the back of the bath!
Have 'lost' both of them on occasion as they will just wander of and not look where we are going and will not be able to find us.
Jumping on the sofas/beds and a special favourite of mine - standing on the back of sofa and divebombing it while I am sitting on it!
This behaviour would be pretty normal for 3 year old say, but 9 year olds? None of their peers seem to do this and when I walk around a shop and see other kids walking round nicely with their parents looking at mine like they are in shock, I just want to cry.
Now they get told off and punished for all this behavior so it's not like I have always let them do this, it's just like a bloody groundhog day all day everyday. They have very good diets, in fact the 'worst' one eats a LOT of fruit and veg as that is his favourite food. Dh sometimes says that it's because I am a vegetarian and while pregnant with them, they did not get enough protein in their brains (am starting to wonder now)!!!! Neither of them have SN btw.