Thank you for writing; I'm sure this is very frustrating for you.
You may want to take a look at Safe Space for Cats for Zorro, which helps the cat establish appropriate boundaries and reduces territorial stress that can manifest as spraying, inappropriate elimination, aggression, or other stress-related behaviors. This formula helps reassure the cat that his territory is safe and protected from intruders from within and without. Zorro may be feeling territorial insecurity because of the foster cats, and this formula can help to reduce this territorial stress.
We formulate Safe Space For Cats using a variety of essences, including Marsh Thistle. Marsh Thistle is known to help those who cling onto old patterns of thought and behavior, and for those who feel fear towards anything new. The essence of Marsh Thistle is known to create a new attitude towards change, an open and welcoming state of mind. The Marsh Thistle essence we use in Safe Space For Cats comes all the way from the small town of Ilkley in Yorkshire, England!
We wish you and Zorro the best!
Our formulas work best when used consistently - meaning tapping the bottom of the bottle on the palm of your hand immediately before administering, 3-4 times a day, and 3-5 drops each time.
Please remember that Jackson Galaxy's Spirit Essences work best when part of a more holistic treatment program, which may include proper veterinary care, diet, behavior modification, and other holistic modalities.