The Moorings does allow ESA animals. To be legitimate it should meet both the following tests.

1) Does the person seeking to use and live with the animal have a disability — i.e., a physical or mental impairment that substantially limits one or more major life activities?

(2) Does the person making the request have a disability-related need for an assistance animal? In other words, does the animal work, provide assistance, perform tasks or services for the benefit of a person with a disability, or provide emotional support that alleviates one or more of the identified symptoms or effects of a person's existing disability?

The ESA classification is heavily abused. As a consequence there are moves in place to require far more documentation. I assume in your case you meet the tests. Keep in mind however that the ESA laws do not apply in the BVI and you may find the dog is not welcome ashore in many areas.
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