Sorry.. this is super long. I am at breaking point with 6yr old DD. I will literally try anything. In short, she is a nightmare.
We have 4 DC, DD1 is 10, DD2 is 6, DS is 2.5 and DD3 is 10months.. Im not sure if thats relevant but just thought I would include it.
These are just some examples of DDs behaviour over the last few weeks.
- She is over excited with both younger siblings and has hurt them both when playing.
- She has forcefully pushed DS away from her when she doesnt feel like playing and has also put her face right infront of his and shouted in his face.
- She constantly annoys her older sister by knocking on her door or shoving papers under her bedroom doors and making whining noises at her and sometimes hitting or calling names
- I discovered a sealed tupperware box in her bedroom that she had peed in and hid under her bed.. when I questioned her she said she didnt know why she did it.
- Her big sister bought her make up for Christmas which I discovered this weekend all over barbies, books and other toys. Its all gone already
- She draws in books, on walls, her toys and furniture. She has also completely wrecked 3 different family games by taking them in her room without permission and losing, ripping or drawing on bits of the game.
- She still has toddler like strops.. if she is told she cant have a snack or something she will throw herself down on the couch wailing.
- Last week she put water all over the bathroom floor with a toy saucepan from her kitchen. When questioned she said she had one saucepan full and her big sister scared her so she dropped it
the whole bathroom floor was soaked
- She lies about things a lot. She told me this week someone punched her at school till I said I would call the school then she backtracked. She lies about her sister hitting her when she thinks Im not looking etc.
Basically she is at the root of all arguments in our house and all the bad behaviour. I just dont know how to deal with her.
I have tried time outs, taking things away from her, shouting, reasoning, no treats and then the other extreme of love bombing.. nothing bothers her.
I am sad to say that when she is at a sleepover with grandparents our household is so much calmer and happier.. I really do not want us all wishing her away, I would love us to all enjoy our time together.
The final straw has come when I just went up to her room. She is extremely messy and last year I was going into her room once a month and helping her sort it all out and get it back to tidy. I did this last just before Christmas and filled two bin bags of stuff from her room. I told her I expect her to keep it tidy herself.. she has labelled boxes for lego, playmobil etc and the floor of her warbrobe and a set of shelves to keep stuff. The boxes that I had filled have been emptied over the floor. She hasnt bothered putting her last pile of clean clothes away and they are now all over the floor mixed up with toys, papers and sticky wrappers (she is not allowed food in her room but she sneaks it up anyway)
I honestly felt like shaking her hard and smacking her.. really hard 
I have come downstairs to calm down. I dont want to feel like this but I am so mad at her.. I just cant get through to her. I have tried so many times to sit down with her and talk to her about her behaviour but she just says she doesnt know why she does it.
Lastly, she does know how to behave because her teacher made a point about how bloody angelic she is in class and so tidy and responsible and was visibly shocked when I said I have problems with her behaviour at home.
Has anyone got any suggestions? I never had anything like this with 10yr old DD and it is seriously making me worried that the younger two could end up like this too. Thanks for getting through the essay 