Black dog and white cat

More than ten years ago, I lived in a bungalow and raised a cat. Of course it was not a pet cat like Persian cat, and I did not name it either. My neighbor had a female cat which gave birth to several kittens. At that time, my daughter was still young and she cried for raising a cat. Touched by the daughter, the neighbor who once declared that they would not give away any kitten, took the initiative to give us one. It was a white female cat. Coincidentally, my neighbor also raised a dog, naturally not a pet dog either, but an ordinary grass dog. It was a black male dog. The elders often said that we should raise female cats and male dogs, but I do not know why.