I remember very well how I dealt with death when I was a child. At first there was terror, because I had serious misconceptions about death. I thought I would still be concious, but unable to move and I feared the boredom and helplessness about that. I can't remember that my parents ever talked to me about that. But now that I am a parent on my own, I wish they had told me that I won't be concious and won't be feeling anymore. So the first thing I would do, is asking your daughter what she is afraid of the most. In a lot of cases you might be able to diminish her fears and remove frightening misconceptions about death.
To deal with the thought of death, I finally came up with my own beliefs that where far more pleasing than being unable to move while concious. I believed that death is just like sleep and that I will permanently live in a dream world.
I believed that every dead being lives there, that the dream world is the home for all souls. These are kind of religious believes, although my parents are not religious at all.
So in case you are religious, it might be good to get into detail of your believes after death as most religions have pleasant views of it. If you are not religious, you can still help your child with explanations that make dead less fearable, like: After death is the same as it was before you where born. You don't remember it, you don't feel it, you don't perceive anything at all. You didn't suffer before you where born, did you?
I also knew as a child that old people are likely to die. I remember refusing to go to my grandmother for the weekend, although I loved her very much. I just feared she would die, while I was there. The thought hurt me a lot and it also hurt that I felt unable to visit her.
This is also something my parents never even got to know, yet I remember it so vividly. I wished someone had told me, that it is very unlikely for her to die, because she wasn't sick at all and didn't have any age related diseases. (Sidenote: She is still alive and very healthy)
So the problem was again a misconception: That all old people are highly likely to die at every given moment. This could have been resolved, if someone had talked to me about that.