Answer: Unfortunately, I am unable to locate a source of information about this plant's toxicity specifically in terms of cats. I have found conflicting reports indicating that either the seeds only are toxic or, the flowers are toxic, or the entire plant is toxic -- but all relating to people.
Since the cat is playing with the plant, I would strongly suggest you contact your veterinarian right away for a professional opinion.
In the meantime, if nothing else to save the plant from becoming shopworn and battered by the cat, you might want to separate the two. In my experience, when a cat takes a liking to particular plant it becomes the plaything of choice and ends up in shreds and tatters very quickly.
Please, check with your vet.
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