Speaking of dogs and cats....
Some years back, I had a small Boston Terrier female. I tried to breed her three times. The first time, she had to have a c-section. The second time, she free whelped. The third time, it was another c-section, so I just had her spayed and gave her to an elderly gentleman for a pet.
The elderly gentleman had a large cat--a tom. The little Boston, who thought that she was a 90-pound Pit Bull, was determined to get rid of the cat. (The cat was bigger than the dog.) If she found him in the front yard of the house, she would chase him out into the street. The cat would circle around the corner, come down the alley, and enter the back yard. If the dog found him in the backyard, she would chase him out into the alley. The cat would go down the alley, circle around the corner, and come back to the front yard. This went on for about two weeks before the dog gave up. After she gave up on running the old cat off, they became friends. They would roll and play together. They even slept together.
I joked with my elderly friend, telling him that I was going to come over and shoot that dog for making friends with a cat--but I was joking.