Dixie does it too.. if she is exited or bored. Sometimes she won't do it for ages and then she does it loads.
And she keeps doing it until she grabs her tail. She gets dizzy you can see her eyes going funny. Lol
Her brother when in rescue did the same they were also worried he had epilepsy but is seems its just a habit they developed, maybe from lack of stimulation as pups- didn't come from too great a home!

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