Unless you buy a cat from a breeder, chances are your cat was a stray at some point in its life. Stray cats experience a variety of problems: no available food, fights with other cats or other animals, a lack of shelter, pregnancy and birthing, or illness. Taking care of these cats is much more trying than take care of a cat that has had a safe home for its entire life.
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Caring For a Psychologically Disturbed Cat