How old is your daughter? (rhetorical)
How old are you, the parent? (rhetorical)
How old are the grandparents? (rhetorical)
Why are the grandparents letting her do whatever she wants? When you entrusted your child to them, is it fair to assume that you have put them in charge of your child, and not the other way around? And if you know that this is going on while you are not there, and you know that is causing the behavior problems, why then are you still allowing them to treat your child like this?
I'm sorry if that sounds snide, but that is the honest truth. You are the parent, you take control.
On to something else you mention. The abuse that went on, and the inability to sleep with out you there... In terms of psychopathology (mental illness, irregularity if the word illness scares you) children are much different from adults in their expression of some things. So, it is hard to say what/why but there is almost certainly a link between the abuse and the sleep problems. (e.g. Post traumatic stress disorder... a common cause of chronic sleep disturbances). However, before running off to a child psychologist saying some undergraduate psychology major said to see you, if you haven't already, ask why she can't sleep alone. Not whether she wants or needs to sleep with you, but why can she? There might be some explaination (e.g. monster under the bed or something). If this is not the case, then seeking professional counciling might be nessicary.
