I'm sorry that you have to deal with this hard fact of life.
Give her time and don't try to rush her grief. It takes time to grieve something you loved very much -- for all of us.
Don't don't try to diminish her pain by saying "it's only an animal" or anything like that.
Don't expect her to "just snap out of it".
Don't rush her to the child psycologist and put her on antidepressants if takes months for her to get over it.
Here are some other tips on grief:
Helping / Supporting Someone Who Is Grieving
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