I have four cats, the two youngest are 3yr's. old. just recently one or more of them has been urinating on my bathroom rug. there haven't been any major changes in the household since the birth of my son two years ago. my cats are strickly indoor and do not come in contact with other animals to cause territory issues. the two cat boxes are cleaned several times a week, usually three times. I have tried some home remedies for the rug, but the smell is still there and they are attracted to that rug now. i don't want to throw it away. i think they will just find a new location to "go." i don't want to and don't have a ton to spend on products. Does anyone have a suggestion for correcting this type of behavior and a successful product for rugs with rubber backs?