I must confess that I have always had cats. I have no children. However, at least for me, my cats were not a cause or consequence of a child-free life. My husband and I both love cats and we cannot imagine our lives without our furry family members in our household.

In fact, our lives with our non-human companions are typical of the average American household. In 2022, the US Census Bureau reported that 70 percent of US households included pets. In contrast, the proportion of households with children under 18 dropped from 48 percent in 2002 to 40 percent by 2022. In South Korea, the difference between the two is similar, but households with pets and/or children are far from ubiquitous. About 30 percent of Korean households reported having at least one pet in 2020, while 23 percent of Korean households included children.

For both the US and South Korea, there is an upward trend in the proportion of households with pets and a downward trend in the shares of households with children. There are many stories of primary schools being shut down and the sales of pet strollers outpacing those of baby strollers in South Korea. In the US, there are occasional articles about the risk to small colleges from the shrinking size of the college population. Of course, this is happening at a much faster pace in South Korea.

If you’re reading this article, I suspect you already know that South Korea currently has the lowest birth rate in the world, at 0.78. In contrast, that rate in the US is 1.66. Replacement level fertility is approximately 2.1, which roughly means that women have to have, on average, 2.1 children in their lifetime for the population to maintain its size. When I was in graduate school in Chicago studying sociology and demography, I could not have imagined fertility rates below 1.0, except in a dystopian science fiction film.

However, correlation is not the same as causation. It would be a stretch to think that pets are somehow the cause of the declining numbers of births and children in South Korea. There are myriad reasons why women and men are rejecting marriage and childbearing in South Korea, but I don’t think pet ownership is one of them. Still, the perception of the compatibility of children and pets may be different in the US compared to South Korea. In the US, dogs and cats are part of the traditional American idealized family that includes a heterosexual married couple with two children living in a house with a white picket fence in the suburbs. Pets and children go hand-in-hand with this image, and animals do not replace children.

For example, there are growing numbers of apartments designed for single adults and their furry companions in addition to the increases in the sales of pet strollers and doggie day cares in South Korea that may hint at how pet owners perceive their pets. It is possible that this relationship between having children and pets in a single household differs in South Korea, where pet ownership is still relatively new and has become more commonplace when birth rates were already dropping.

While I was rewatching the K-drama "The Glory" recently, the main male villain, Jeon Jae-jun, (spoiler alert!) discovers that he has a daughter with the main female villain, Park Yeon-jin. He fantasizes about taking custody of his biological daughter. The audience sees a worker remodeling a room in Jae-jun’s apartment in preparation for her. Jae-jun’s beloved dog Louis XI runs into the room, and the worker says to Jae-jun: “People with children generally don’t have dogs because the fur can cause allergies.” Jae-jun’s reaction is terrifying as he menacingly stares at his dog.

We suspect that the dog will meet an unkind fate from this inhumane owner. This scene also strips the character of his only redeeming trait (his love for his dog). I later found that this scene struck a nerve with audience members. Perhaps Jae-jun would have never gotten the dog if his daughter lived with him -- this would be an example of children displacing the possibility of pets and not the other way around. In fact, I know of many people with children whose pets were sent away once their children arrived and developed allergies or asthma.

Pets in the household provide love and companionship, and individuals enjoy all types of physical and mental health benefits. Many of us talk to our pet companions and take comfort in petting and playing with them. Children are much more difficult to manage, but they offer very different rewards to their parents. Parents would not choose their pets over their children, but they would choose their children over their furry companions.

If the decision to welcome an animal into one’s household led to lower birth rates, one thought experiment might be this: If pet ownership were somehow outlawed in South Korea, would people suddenly have more babies? I doubt it.

Grace Kao

Grace Kao is an IBM professor of sociology and professor of ethnicity, race and migration at Yale University. -- Ed.