My grandson is very moody but improving as he gets further into his teens (he is 14), but now my almost 11 year granddaughter has started as well! All I can say it that it does pass - there is a lot of pressure on children today, they are teased and tormented at school and in peer groups if they don't fit in and/or have the latest 'must have' item, they have to master using computers for school and homework too and I think expectations are generally greater for their future, which only adds to the pressure. Add to that the fact that she may not only be missing her grandfather but also upset that you are hurting from his loss and I think you can see that, perhaps, acting out in this way is her way of dealing with things. My advice would be to not take it to heart (I'd be living in the Artic if I had walked a mile for every mile my grandson has told me to go away when he's having a hissy fit ), keep a sense of humour about it if you can, it will pass and she may well turn out to be a loving and caring granddaughter again at the end of it. No parent likes being told that their child is misbehaving, you had your say and I think your DD is right that you should now let it go now. Your own feelings are going to be more sensitive because of the short time since the loss of your DH