You mentioned he has really thinned out the past six months... Have you taken him to a vet? After age 12, a couple things can make them thin -- kidney disease and thyroid. Both have treatments for them (they have food that can help slow kidney diease and meds help thyroid). I recommend taking him to the vet, he could very well have something they can help treat to give you more time with him...
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Tammy and Pookey
(Stanley 8/91 - 8/07)