You said you had a problem with one of your cats using the litter boc, which I think is 10 years old. Is this a male or female? Sometimes they do not use the litter boc because os their kidneys or infections, but if the blood levels are fine for kidney functions, then it"s something else. Good luck to you. Hope everything is ok with your cat.
How are ya doin' Inkypoodle? It's been awhile since I've been here, so just thought I'd stop by to say hello. Also wanted to check out your lovely cat pics. This is a wonderful shot...and Doodles is certainly a beauty!