What does the phrase "a cat two dog" mean?

It should be "cats and dogs alone" This is an old saying in the past. The older generation thought that the mother cat gave birth to two kittens and the mother dog gave birth to only one puppy. These cubs will be the best. It means that the mother cat gave birth to two kittens and the mother dog gave birth to a puppy, which is unlucky and the owner's family doesn't know, but it's just a superstition handed down, just like some people say that dogs are good, and suddenly a dog comes to your house, which means that your family is about to make a fortune, so it is better to cross it. This is only a subjective idea and has no scientific basis.

There are more and more cats and dogs, which means that it is good for cats to have two cats, which means that it can bring good luck. Generally, you don't give it away or sell it. It's good to have a dog.