Cat haters often mistreat cats which produces mean cats which confirm to the cat hater's warped opinion of cats. Mean unhappy people with mental issues will produce mean unhappy cats with mental issues.
Not completely true. Cats come in a variety of temperaments and it's usually how they were handled during their first few weeks as a kitten that will leave a lasting impact on it's behavior. Also, cats need to have their own space. Sometimes the lay out of the home can affect a cat's behavior.
Personally, I never trust any animal around children.