Last March, when Odyscea Kian, an at-home mother in Gainesville, Fla., began warning her eight-year-old son, Roman, about a contagious and potentially deadly new virus, he seemed OK — at first.

The family, she told him, will not be traveling to his grandfather’s house in Miami to celebrate Iranian New Year like they usually do. He might become infected, but not know. He won’t be able to go to school or see friends for, well, who knows how long. But he can still enjoy bike rides around the neighborhood or swimming in their backyard pool.

For the first month or two, Roman appeared fine with life in the bubble, as he hunched over the dining room table for hours writing screenplays for a stop-action film starring his “Star Wars” figurines. As the months dragged on, however, he seemed a little too fine with life inside the bubble.

“Now,” Ms. Kian, 37, said, “he doesn’t want to leave the four walls of this house. He doesn’t even want to go to the backyard. If I want him to go with the pool, I have to beg.”

“My son,” she added, “who was a pretty introverted kid pre-Covid, has turned into a hermit.”

After more than a half-year of virtual house arrest, some adults crave nothing more than escape into the broader world beyond four walls. For some younger children, however, the topic is a little more complicated.

Faced with a world of ominous warnings, masks, and playgrounds barricaded by yellow tape, some crave the security and familiarity of home — so desperately, it seems, that parents find themselves resorting to pleas, threats, or bribes to drag them out of the house, with highly mixed results.

And parents hoping for a return to normal with the new school year may be disappointed, as many schools nationwide have adopted strict and potentially unsettling social-distancing measures, complete with masks — that is, when schools are open at all (This month, Mayor Bill de Blasio of New York announced he would close all schools — public and private — in nine of the city’s ZIP codes, which were experiencing high positive test rates).

The result is yet another worry in a year of worries for parents. As if the ever-present tussles over screen addiction and remote schooling were not enough, now some wonder if they are doomed to raise Generation Agoraphobia.

“This phenomenon is incredibly widespread,” said Nina Kaiser, a child psychologist in San Francisco whose team of nine therapists specialize in anxiety-related issues. “We’ve been hearing these concerns from families in our own practice, and done a ton of webinars with pediatric practices, and in every one there are questions about kids who are reluctant to leave the house and how to coax and cajole them.”

And who can blame them? “For months, our behavior has sent this message that the safest place to be was at home,” said Dr. Kaiser, who added that she is dealing with the same issues with her four-year-old son. “So it’s hardly shocking that we’re seeing significant pushback from kids about leaving the safe zone.”

Even adults have a hard time calibrating the relative safety of any trip into public. How can we expect a seven-year-old to know?

“For younger kids, it’s hard to do a risk analysis,” said Golda S. Ginsburg, a professor of psychiatry at the University of Connecticut. “They’re just not cognitively mature enough. And children who struggle with anxiety can overestimate the risk and underestimate their own coping skills.”

“For some kids afraid of leaving the house,” she added, “they are terrified there is nothing that they can do to be safe or reduce their anxiety — so they stay indoors.”

An ever-changing environment

Some children develop their aversion slowly. For others, the change is abrupt.

Marki Stewart, 39, a lawyer in Phoenix, said there was no question when her eight-year-old daughter transformed from a child that eagerly headed for Ninja exercise classes and the toy aisle at Target to a homebody in the extreme.

“As soon as Covid hit and school shut down,” Ms. Stewart said, “it was like a switch flipped — she refuses to leave the house.”

At first, that stubbornness was actually convenient. “We couldn’t go anywhere or do anything because of social distancing,” Ms. Stewart said, “so it was helpful that she didn’t want to go anywhere or do anything.”

However, any attempt that she and her husband make to get the child out for daily walks for exercise devolve into 30 minutes of fussing, cajoling, and bribery, or outright refusals, Ms. Stewart said.

The two times they managed to get her out in public since quarantine and walk her to a nearby bookstore which they assured her was empty and safe, “she whined constantly that she wanted to go home,” Ms. Stewart said. “The last time, she grabbed the first book she saw and said, ‘OK, can we go now?”

The mask itself can be a reminder of lurking danger beyond the front door.

“My daughter is afraid of anyone in a mask because it reminds her of doctors and hospitals,” said Elizabeth Copland, 34, an academic counselor at the University of Washington who lives near Seattle.

While the daughter, Elodie, who is 2, usually clings to her mother “like a barnacle” at the thought of leaving the house, Ms. Copland recently managed to get her outside for a walk. When they ran into a friend, “my daughter didn’t recognize her in her mask and immediately burst into tears.”

Is this actually agoraphobia?

Much of this resistance among children to leave the house does not, in fact, meet the clinical definition of agoraphobia, said Mary Alvord, a psychologist in Chevy Chase, Md. who works with children dealing with anxiety-related issues.

According to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, agoraphobia is an anxiety disorder that involves a fear of being in places where escape might be difficult — a crowded train station, say, or a subway train — which can lead to feelings of helplessness, and at times, panic attacks.

“Agoraphobia is really the fear of leaving the house alone, or of being in crowded places, but there has to be an intense fear,” Dr. Alvord said. (It is more common in teenagers than younger children, she added).

While phobias can develop if a child falls into a pattern of resistance and avoidance, specific phobias are often rooted in a single negative episode — a bee sting that might make you phobic about being outside, for example.

But, Dr. Alvord said, “there are some kids who just don’t want to leave home because it is so comfortable. For them, it’s the path of least resistance more than fear: ‘No, I’d rather stay home, text with my friends, and play video games with them over a server.”

The comforts of being home vs. the scary outdoors

After four months of near-confinement in a two-bedroom apartment in Park Slope, Brooklyn, Shruti Kapoor, who runs a nonprofit organization for women in India, noticed that her 4-year-old daughter, Diya, lost any desire to leave the house, seeming to prefer time with her parents.

“Whenever I asked her, she said she was never afraid, she was just comfortable at home,” Ms. Kapoor, 42, said. “But there was a very clear point where she was itching her body, or scratching her face, like she was nervous or anxious. I think it was about being cooped up, and a lack of engagement.”

That was also the experience of Adam Craniotes, 48, a magazine editor in New York.

After a temporary stay in Connecticut last spring, where his children Paul, 13, and Lola, 11, happily ventured out on hikes in the woods or to go crabbing at the beach, they returned to New York City in June where his children were confronted with new and alarming urban protocols: only their mother, Liz Chen, wearing disposable rubber gloves, was permitted to push elevator buttons; visits to their grandmother uptown were hug-free, and everyone had to wear masks, even indoors.

“It was like pulling teeth to get Paul and Lola to leave our apartment for, well, anything,” Mr. Craniotes, 48, said. “They were only too happy to binge-watch Netflix and Disney+ and FaceTime with their friends, or Paul’s case, play online video games.”

No wonder. In games like Roblox, which has seen a surge of interest among tweens and pre-tweens during the pandemic, children can explore the great cities, throw raucous parties, and start garage bands in a colorful world where everything seems free (except, of course, when those eye-popping in-app purchases show up on their parents’ credit card statements).

Compare that to the world of shuttered libraries, movie theaters and gyms that exists outside their bedroom windows.

Before relocating, perhaps temporarily, to Westchester County in August, Jenna Yasgur, who owns a wedding calligraphy business, and her husband Jon Yasgur, an advertising creative director, found their daughters Clementine, 9, and Georgette, 7, showing little interest in leaving their “terrarium of an apartment on the 24th floor looking out at the quiet bleak streets of Brooklyn,” Ms. Yasgur wrote in an email.

Where would they go? Their favorite haunts like the Natural History Museum and Color Factory, a Technicolor art space, were closed, after all.

“They would just want to pour themselves into the cool obbys of Roblox,” said Ms. Yasgur of the gaming site and app with virtual worlds filled with Lego-like characters. “It was their alternate reality where they could be at amusement parks, create lemonade stands, adopt pets, trade things with friends, actually dress up their avatar, because no one in the house was even getting dressed these days.”

What can parents do to help?

Bribery can seem like the only option to some parents who have a hard time luring their children outdoors.

For Maggie Van Ness, a senior project manager at a running shoe company in Seattle, any attempt to get her daughters, ages 10 and 6, some fresh air (such as it is, with nearby wildfires), turns into a collective bargaining exercise.

“For them, it’s ‘what’s the incentive, what’s the reward?’” Ms. Van Ness, 46, said. “ For my younger daughter, ‘snack’ is the magic word: Can we go to Starbucks to get a cake pop? But we’ve tapped out on all the tricks. Now it’s more like, ‘if we had that puppy, sure we could go out for a walk.’”

The nudge, push or the bribe may be worth it if parents want to break their children’s homebody habit.

After all, an anxiety disorder may, in theory, develop if children fall too deeply into a pattern of avoidance of the outdoors, Dr. Ginsburg said. “It’s important to identify the cause of the anxiety. For some kids, the fear is separation — something might happen to me or my parents if I leave the house.”

Whatever the specific fear, she said, “the core treatment ingredient of anxiety disorders is really to do the opposite of what they’re avoiding.”

Gradually, but emphatically, parents should make every effort to get their children out of the house, to travel “over and over and over, and farther and farther and farther,” Dr. Ginsburg said. “Let’s walk to the end of the block. Now let’s walk around the block.’ And after they do face their fear, parents can talk it through: ‘Did you have fun? What was really positive about going out?’ and build on the successful experience.”

Several parents interviewed wondered if this avoidance of the outdoors might have lasting mental harm.

“Kids are incredibly resilient,” Dr. Kaiser said. “A lot of the long-term impacts depend on how we message that transition as we start to go back to normal. Try not to be reactive, and send the message that this is a bigger deal than it needs to be. Steer away from validating kids’ desire to stay home.”

And for the present, letting them indulge in a little fantasy exploration is not a bad start.

When Symon Hajjar, who runs a children’s music program in Tulsa, Okla., tried to coax his two young sons Isaac, 5, and Ezra, 3, to buy some plants for the garden at a local nursery a few months ago, he was encouraged to learn that they had already planned a trip of their own to Oklahoma City — without leaving the family property, that is.

“My wife and looked out into the backyard and the kids had arranged all the benches around the fireplace into airplane seats, packed their suitcases full of cheese sticks and apple sauce packs, and surrounded themselves with all their stuffed animals as passengers,” Mr. Hajjar, 39, said. “They must have been on that flight for an hour.”