Question from Cathy:
My 5 year old cat just started hissing and fighting with her mother cat. I can't figured out why now all of a sudden, no changes in the household, she won't allow her near me, on the window sill, or near the scratch toys. They are both indoor cats.
Answer from Amy:
Cat aggression usually comes from situation when a cat wants to dominate (offensive aggression) or feels threatened (defensive aggression), but first of all we have to know that it is never the cats' interest to be involved in an aggressive fight because cats are very cautious about their safety and like to conceal their vulnerability from others. That's why it is hard to read if a cat is having any discomfort because they are masters at masking pain but that's a different story (Cats are masters at masking pain)
Usually a cat fight involves hissing, swatting and a bit of wrestling and biting, but they never bite into each other very hard and usually get separated when one cat surrenders and leaves.
Cats like to send warning signal through staring, walking with the hindquarters lifted, turning the ears flat to the side, etc.. However, these usually happen for purposes such as territory rights or for food.
Sometimes cats fight or even bite when they play. If they get really aggressive, you can clap your hands really hard, the loud noise will separate them apart. However, if they continue to grapple, you will need to keep them in two separate rooms until they cool down. Never physically intervene or engage in a cat fight because they may turn their aggression towards the mediator.
In your case, it sounds like your 5-year-old cat is being territorial against her mother by blocking her entries to the window sill and the scratch toys. The reason that she won't let her mother near you is because getting human attention is one of the ultimate ways for a cat to show dominance to other cats in a multi-cat household.
Taking over the window sill and the scratch toys also show a sense of territorial instinct. Sometimes cats reaffirm their status in a multi-cat house hold by having bouts of aggressive behavior towards each other. They are usually mild fights which do not necessarily require human intervention. Cats need to have their status established in the house because they naturally live in a hierarchical society.
Aggression should never be seen as their fault and cats should never be punished because of that. What you can do to reduce conflict in the house is provide a secondary scratching post or another window sill for the mother cat to perch on. Reward your 5-year-old cat with her favorite treat and soothe her by petting when the mother cat comes around. Soon she will associate the mother cat's being near you, the window sill or the scratch toys with a positive, pleasant experience.
I doubt your 5-year-old is mad at her mother. It is very likely that her aggression is a result of her way to show dominance.