Gosh, Lara, it does sound as if she's getting some sort of evil pleasure from all this, but I'm really glad you're having her checked by a vet. Be sure to describe all those behaviors. They could have an organic basis.
I suspect she ignores your daughter after a bit because she knows the girl will be leaving soon. She doesn't want to get attached again.

Perseverance!
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I've had a bunch a cats, & when I can manage to be as stubborn & as imaginative as they are, we can usually work things out. These folks here have good ideas, & 1ce you've gotten any medical input they'll help you with a plan. Me too.
Your kitty is adorable. My 21-yr-old gal passed recently, so I adopted a 14-yr-old & a 7-yr-old whose owners had died. Turn about & karma, eh?
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