You can try Felaway...
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We have several cat boxes... 4 for 2 cats. This seems to help us at least.
Do the other cats use HIS box? Since he is at the bottom of the pecking order, the Felaway may work for him. It reduces cat stress.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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