hello cleocatra,
this does seem to be a problem and sometimes it's hard to pinpoint what is causing it. You might want to check a previous posting called pee on old carpet pee on new carpet, for there are some suggestions there. http://petoftheday.com/talk/Forum9/HTML/000055.html
This can be a frustrating thing for a cat owner, especially if you don't know the reason for the behavior.

What you described sounds like a behavioral problem. you mentioned that your brother adopted this cat from a friend who just had a baby? that could be the cause right there. major life change in the cat's environment. suddenly the cat is living in a new place and is probably a little confused as to why it's original mom gave her away! you might want to inquire the previous owner about the broken tail also. was she abused?

i would definitely take her to the vet and describe the behavior and the events leading up to it. he may be able to help. be sure to keep us posted! i hope everything gets better for your brother and Mogwai!!

welcome to pet talk! i hope you enjoy it here

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"In a cat's eye, all things belong to cats." - English proverb