Is there truth behind the "fight like cats and dogs" idiom?

Each product we feature has been independently selected and reviewed by our editorial team. If you make a purchase using the links included, we may earn commission.

Deciding to add another cat or dog to your family is a choice that feels equal parts exciting and nerve-wracking, particularly if you already have a feline family member at home. You want to make sure that the new addition gets along well with your resident cat, which can sometimes be more involved than you think. Here's how to help start the new relationship on the right foot.

Choose Wisely

Unfortunately, there's really no magic formula to determine if your cat will get along with other pets, says Dr. Jennifer Goetz, DVM, and owner of Manlius Veterinary Hospital. However, she says the good news is that much of the success depends on the way in which you introduce the two animals. If you're adopting another cat, Dr. Goetz says there's no firm answer about if gender selection matters, though in her experience she's seen cats get along better with cats of the opposite gender.

If you're adding a dog to your family, she says gender and size typically don't matter, and that "the majority of cats and dogs get along decently well. There's not much truth to the 'fight like cats and dogs' saying."

You should be aware of the dog's breed, though. Dr. Goetz explains that some breeds were specifically trained to chase after small animals, making them a less-than-ideal match for a home with a cat. This includes greyhounds and Italian greyhounds.

Prep Your Cat for the New Arrival

While Dr. Goetz emphasizes that the introduction is the most crucial part in determining how the two animals will get along, she says there are a few products you can use to help keep your cat calm when meeting his new furry sibling for the first time.

She recommends Feliway, which comes as a diffuser or in spray form and has pheromones that can keep cats calm and reduce stress. You can also buy a calming collar to create the same effect.

Move Slowly

When it comes to introducing cats to a new furry family member, you'll want to take your time. Dr. Goetz says it can take weeks or even months for pets to get acquainted.

"People get into trouble when they try to make it speedy," she cautions.

If you're introducing your resident cat to a new feline family member, here are a few steps to follow:

  • Give the new cat its own space: Ideally, this is somewhere where you can close a door, like a spare bathroom. Put down food, water, and a litter pan. If you’re living in a smaller space, get a large dog crate and put these essentials in it along with the new cat. Then cover the carrier with a sheet or towel to give the cat a sense of privacy.
  • After a few days, switch the two cats’ positions: This means the new cat will have the run of the home, with the resident cat in the spare bathroom or carrier where their new sibling just was. This allows each cat to get familiar with the other’s scent in a non-threatening way. 
  • Then, wait a few days and introduce the two: When the cats are able to get familiar with the other’s scent first, it can minimize tension during a face-to-face introduction. 

As for introducing cats and dogs, Dr. Goetz recommends keeping the pup on a leash and letting the cat investigate and get comfortable for a while. When you're sure that the dog won't start chasing the cat when unleashed, you can let the two interact more closely. Your cat's first instinct when the dog is unleashed may be to hide, which is okay. 

Don’t Be Afraid of a Little Wrestling

While it's probably frightening to see your cat engaged in a scuffle with the new cat or dog you've adopted, Dr. Goetz says that some physical contact as the two animals meet for the first time is normal. A cat may growl or hiss at its new companion or pop him across the face. However, if you see one pet pinning the other down or trying to cause harm, it's time to break up the contact immediately. And until you're sure that the animals will get along, don't leave the two pets out and about together while you're not home.

Don’t Expect a Disney Movie

While you're probably imagining furry sibling cuddles and play sessions, in reality, it's best to go in with moderate expectations about how the duo will get along. 

"I think minimally you should be able to have a smoothly functioning household with at least civility. Some cats and dogs end up being best buds. Others just tolerate each other," explains Dr. Goetz.

WATCH: Why You Should Pack a Pet Emergency Kit

If several months have gone by and the two pets still aren't getting along, Dr. Goetz recommends getting in touch with your vet. They can assist you in trying to identify the problem so that everyone can co-exist peacefully.