Children love their pets—and for good reason. Creatures both large and small teach, delight and offer a special kind of companionship.

Everyone knows that kids love animals. They permeate childhood media. In real life, an estimated 4 in 10 children begin life in a family with domestic animals, and as many as 90 percent of all kids live with a pet at some point during their childhood, says Gail F. Melson, Ph.D., professor emeritus of developmental studies at Purdue University and the author of Why the Wild Things Are: Animals in the Lives of Children.

The amount of money we spend on pets has nearly doubled in the past decade, rising to more than $38 billion, according to the American Pet Products Manufacturers Association. That figure dwarfs the toy business ($23 billion) and candy industry ($24 billion).

Because my wife and I grew up companioned by animals, we are delighted with our daughter’s natural zeal and passion for critters. Our current menagerie includes one German shepherd, one Yorkipoo, three cats, three goats, a freshwater aquarium and a tank of Sea-Monkeys, a hybrid species of brine shrimp. Living in the woods, we’re paid an endless series of cameo appearances by turtles, mice, moles, frogs, toads, tadpoles, ducks, geese, slugs and other wildlife.

Like most parents, we counted on the commonsense idea that having animals around would help teach our daughter responsibility and maybe, empathy. But, we’ve also learned that the presence of animals helps foster her emotional, cognitive, social and physical development.

Plenty of solid evidence backs up such observations. Following are five reasons to let the fur fly in your home.

Pets Aid Learning

We often find our daughter curled up in her bed or lying in a den of blankets in a quiet nook of the house, reading to one or more of her cats. She pets them as she reads, stops to show them pictures and asks them questions. She even reassures them during scary parts of the story.

Educators like Mary Renck Jalongo, Ph.D., education professor at Indiana University of Pennsylvania and author of The World of Children and Their Companion Animals, have long known that bringing therapy animals (mostly dogs) into schools helps developmentally challenged kids learn. Now they are finding that all children can benefit from the presence of a nonjudgmental pal with paws.

In one of Jalongo’s studies, children were asked to read in front of a peer, an adult and a dog. Researchers monitored their stress levels and found that kids were most relaxed around the animal, not the humans.

“If you’re struggling to read and someone says, ‘Time to pick up your book and work,’ that’s not a very attractive offer,” Jalongo says. “Curling up with a dog or cat, on the other hand, is a lot more appealing.”

Pets Provide Comfort

In another Jalongo-led study, children were asked what advice they would give less-popular kids for making friends. The top answer didn’t focus on a cool toy or must-have sneakers. It was: Get a pet. Whether a hamster or a horse, Jalongo notes, an animal gives a child something to talk about and a shared interest with other kids.

Animals are also a great source of comfort. Melson asked a group of 5-year-old pet owners what they did when they felt sad, angry or afraid or when they had a secret to share. More than 40 percent spontaneously mentioned turning to their pets. She remarks that, “Kids who get support from their animal companions were rated by their parents as less anxious and withdrawn.”

Pets Encourage Nurturing

Melson began studying the impact of pets in order to learn how human beings develop the ability to care for others. “Nurturing isn’t a quality that suddenly appears in adulthood when we need it,” she observes. “You don’t learn to nurture, because you were nurtured as a child. People need a way to practice being caregivers when they’re young.”

In most of the modern world, there’s little opportunity for kids to provide for other living things aside from pets. “In many other countries, siblings look after one another, but in the United States that’s not culturally acceptable,” Melson says. “It’s actually illegal in many states to leave kids in the care of anyone who is under 16 years of age.”

So, how are the seeds of good parenting skills planted during childhood? Melson believes one way is through pets. In her research, she tracked how much time kids over age 3 spent actively caring for family animals, versus caring for or even playing with younger siblings. Over a 24-hour period, pet guardians spent 10.3 minutes in caregiving; those with younger sibs spent only 2.4 minutes.

“Nurturing animals is especially important for boys, because taking care of an animal isn’t seen as a ‘girl’ thing, like babysitting, playing house or playing with dolls,” Melson says. By age 8, girls are more likely to be involved than boys in baby care, both inside and outside the home, but when it comes to pet care, both genders remain equally involved.

Pets Help Keep Kids Healthy

According to a study by Dr. Dennis Ownby, a pediatrician and head of the allergy and immunology department of the Medical College of Georgia, having multiple pets actually decreases a child’s risk of developing certain allergies. His research tracked a group of 474 babies from birth to about age 7. He found that the children who were exposed to two or more dogs or cats as babies were less than half as likely to develop common allergies as kids who had no pets in the home. Children with animals had fewer positive skin tests to indoor allergens—like pet and dust mite allergens—and also to outdoor allergens, such as ragweed and grass. Other studies have suggested that early exposure to animals at home may decrease a child’s risk of developing asthma.

No one knows for sure why this is the case, but Ownby has a theory: “When a child plays with a dog or a cat, the animals usually lick him,” he says. “That lick transfers bacteria that live in animals’ mouths, and the exposure to the bacteria may change the way the child’s immune system responds to other allergens.”

How Pets Build Family Bonds

One of the biggest benefits of having pets is often unexpected, even for parents who grew up around animals: They can help families grow stronger and closer. “Whenever I ask children and parents if their pets are truly part of the family, most of them seem surprised—and almost offended—at the question,” Melson remarks. “The most common response is, ‘Of course they are!’”

A pet is often the focus of family activities. Everyone takes the dog for a walk, shares in the grooming and feeding or gets down on the floor to play together. Kids can even benefit from simply watching a cat chase her tail or a fish swim in his tank. Spending time like this offers the potential for slowing the hectic pace of the day.

If someone asks what we’re doing, we might respond “nothing.” In an era of overscheduled children and parents constantly on the go, “nothing” can be an important thing to do.

Bill Strickland, a freelance writer in Emmaus, PA, recently published his memoir, Ten Points. He regularly contributes to national publications.