'Until she found out it was male' poo.. Poor fella.
You seem to have already decided against it, you just want reassurance that you're doing the right thing.
And I think you seem pretty aware of the outcome of getting a new kitten.
It definitely sounds more like a novelty in my opinion, and I think if it were me, I would have to say no to her.
Its a bit difficult to explain to a child that a cat will never really belong to one person, it becomes part of the family
like a brother or sister, and isnt an object that someone can take claimship of.
With other cats in the house, it would most likely grow up to be far less reliant on her than she would like,
And she would probably be better off with something that requires more interaction/care, like (as mentioned) a rabbit
or a guineapig, or a hamster. Cats are a long term commitment, as we all know.
I would probably start her with an animal that did not live as long, to teach her ownership and responsibility
without the long term commitment of a cat.