I don't know if anything changed in your daughter's behavior.
I have myself one very difficult tree years old child. She is hyperactive, always asking for one or another thing, never giving up till she got it and than lousing her interest completely, ask for another.Keeps me busy all the time.
Psychologists say that a parent should ignore that behavior, or turn the attention of the child to a someting else.If you try you'll see that it works...just sometimes.
With my child, if I pretend that I'm crying, she shows some sensitivity. I know, that's emotional blackmail, but kids should know that their actions are not without consequences.
I guess each child has his own way to be treated. We can just give some ideas to each other. So, if you found some solution, just write