Growing up is hard to do when you want to stay forever young.

“Vanderpump Rules” star Jax Taylor, Thomas Ravenel of “Southern Charm” and the ever-rotating cast of “Bachelor” heartthrobs all appear to be suffering from the same thing: “Peter Pan Syndrome.” This pop-psychology concept (also known as puer aeternus, Latin for “eternal boy”) describes adults who are socially immature. And because of this “ailment,” they were made for reality television stardom.

Dr. Dan Kiley coined the term “Peter Pan Syndrome” in 1983 after noticing a rise in irresponsibility, anxiety, loneliness, narcissism, chauvinism, social impotence and despondency in his patients. “It’s not life-threatening, so it’s not a disease. But it endangers a person’s mental health so it’s more than an inconvenience,” Kiley wrote in “The Peter Pan Syndrome: Men Who Have Never Grown Up.”

He also noted that “victims” of “Peter Pan Syndrome” fought to balance being devoted to and despising their partner, acting gregariously and feeling lonely, and most notably, being faithful and being flirtatious — behavior very familiar to anybody who has tuned in to reality television.

“When [they are] casting a show like ‘The Bachelor,’ oftentimes producers look for people with more intense personalities,” Dr. Jenn Mann, the executive producer and host of VH1’s “Couples’ Therapy with Dr. Jenn” and VH1’s “Family Therapy with Dr. Jenn,” told Page Six, noting that the ideal person has “less impulse control, [is] more likely to create conflict and make for interesting TV.”

When looking to cast the next Taylor, Ravenel or his “Southern Charm” co-star Shep Rose, Dr. Venus Nicolino, the host of “Marriage Bootcamp: Reality Stars,” told us producers are often looking for “someone who’s egocentric. Someone who’s non-committal. Narcissistic. They see responsibility as a burden or inconvenience.”

And there’s a reason that these responsibility-eschewing personalities can get away with it.

“Culturally we’re going through a developmental shift. People are taking much more time to grow up, which would make sense given that people live longer,” she explained.

Jax Taylor, the 38-year-old, hot-headed bartender from “Vanderpump Rules,” is known for balancing his romances with younger co-stars with his taste for infidelity. He entered the zeitgeist in January 2013 as a staffer at Lisa Vanderpump’s West Hollywood restaurant SUR, and he was dating his then-23-year-old co-star Stassi Schroeder. Their relationship crumbled after he lied about cheating. He vowed to better himself and attempted therapy, where he revealed he was living an even bigger lie: Jax Taylor was actually Jason Cauchi. The reality star had changed his name in hopes of pursuing a modeling career in Miami.

Come Season 2, Taylor was desperate to win Schroeder back, but instead slept with her best friend, Kristen Doute. Four years later, Taylor’s shacked up with Brittany Cartwright, a 29-year-old Hooters waitress from Kentucky. During the show’s Season 6 premiere, it was revealed Taylor cheated on Cartwright with a former SUR staffer, Faith Stowers.

Again, he vowed to change his ways, seeking alternative therapies like Reiki healing, but according to Dr. Jenn, his repeated behavior signifies something else. “It sounds like he’s not happy with how his life is going but he’s also not doing anything differently,” Dr. Jenn told us. “And in order to do something different, then a lot of the time people need therapy to kind of break out of old, bad patterns.”

A few episodes later, Taylor is shown in a rare moment of self-awareness. “There’s really nothing here for me,” he tells Cartwright after being approached about a job with a hockey-related outlet in Tampa. “I’ve been living, like, this Peter Pan lifestyle for so long that it’s just like —”

“I’m ready for you to grow up too, so …,” she says with a laugh.

Later in the episode, Taylor is shown telling co-stars Tom Sandoval and Tom Schwartz “we gotta grow up.”

“I hate saying that,” he says. “For me at 38 years old, not having a college education, I need to have some kind of structure. Some kind of security … I need to have something in my life at 40 years old … I’m still living this ‘Peter Pan Syndrome’ and I cannot escape it. I’m falling into the same patterns that I used to do and I’m ready for something else.”

At press time, Taylor is still living in Los Angeles with Cartwright. He did not get back to us for this piece.

Thomas Ravenel’s “Peter Pan” ways predate his stint on “Southern Charm.” The now-55-year-old had a career as a South Carolina state treasurer prior to appearing on the reality show, but it was cut short after he was charged with cocaine distribution in 2007 and subsequently sentenced to 10 months behind bars in 2008. In 2013, he pleaded guilty to DWI just before the show’s debut season.

While Bravo’s cameras were rolling, Ravenel proved that age is just a number as he notoriously partied alongside his much younger co-stars, including Rose, 37, Landon Clements, 35, Cameran Eubanks, 34, Craig Conover, 29, Kathryn Dennis, 25, and Naomie Olindo, 25.

Despite their 30-year age gap, Ravenel and Dennis would go on to become romantically involved and welcome two children together, Kensington Calhoun Ravenel, 4, and St. Julien Rembert Ravenel, 2. He’s since moved on from Dennis — and narrowed the age gap — with 32-year-old Ashley Jacobs.

“Having the man be older and female be younger is traditionally what we see in society,” Dr. Nicolino said. “In the 1950s, [age differences like this] would be commonplace. Really in the ’70s, ’80s and even the ’90s. [It’s] incredibly common … [but] when you’re viewing it on reality television, perhaps it’s shocking to us now because we’re beginning to see such a gender shift in men’s and women’s roles. So now it’s kind of like, ‘Wait a minute, you a——s … find somebody your own age!’”

Bravo declined to comment about their aforementioned shows.

On “The Bachelor,” women ranging from age 22 to 33 compete for the affection of a man who is often significantly older than they are. “With ‘The Bachelor,’ when you have a guy in his 40s and … mostly women in their 20s … that’s a casting decision,” Dr. Jenn said.

In 2004, Byron Velvick appeared on the ABC hit at age 40. More recent “Bachelors” Nick Viall and Arie Luyendyk Jr. were both 36 years old during their seasons, when they romanced women as young as 22.

Other gaps in “Bachelor” history include 21-year-old dental assistant Mackenzie Deonigi, who competed for the love of Chris Soules, who was 33 in 2015 and former NBA dancer Cassandra Ferguson, also 21, who tried to win the heart of Juan Pablo Galavis, 32, in 2014.

“It’s a substantial age gap in that time in your life,” Dr. Jenn said. “If you look at evolutionary psychology, there are reasons why couples with big age gaps often come together. Women are attracted to older men because they’ve been around longer. They’ve had a longer time to gather resources and [if] we’re looking at successful men which are on ‘The Bachelor’ or on ‘Southern Charm,’ then oftentimes that has an appeal.”

But on “The Bachelorette” — where a number of male contestants compete for the love of one woman — age gaps are much smaller. Recent couple Jojo Fletcher, 27, and Jordan Rogers, 29, are just two years apart, while there are seven years between Bryan Abasolo, 38, and Rachel Lindsay, 31. (ABC didn’t return a request for comment regarding casting practices.)

As for men, “a lot of the time they’re looking at the aesthetics and childbearing years and when women are at their most fertile and oftentimes they are attracted to women in their 20s for those reasons,” she explained.

And on shows like “Keeping Up With the Kardashians” and “The Real Housewives of New York City,” women are playing the same game.

Kourtney Kardashian, 38, and Scott Disick, 34, dated for nine years as documented on “KUWTK” and welcomed three children together. After their split, Kourtney moved on with Younes Bendjima, 24. Meanwhile, her sister Khloé, 33, is expecting her first child with boyfriend Tristan Thompson, 27.

“Real Housewives of New York” star Carole Radziwill, 54, dated chef Adam Kenworthy, 32, for two years despite her Bravo co-stars giving her a hard time about their age difference, which only highlighted the double standard many women face when dating younger men.

“A woman would be laughed at or maybe even scorned and judged for dating a man 20 years younger, and a man would be put on a pedestal for that,” Dr. Nicolino told us. “What it really displays is a redistribution of resources and power.”

“While we have all of these multiplying Peter Pans, guess what we have? We have multiplying Wendys,” she explained. “Women who take on the role of caretaker … when we see older women with younger women, we’re still like, ‘Oh my God, I can’t believe she’s dating someone 10, 15, 20 years younger than her,’ but at the same time, [it is] possibly a good thing because what it says is that there’s a redistribution of resources. Women now have power to be a sugar mama. It’s a redistribution of resources. The only reason we find older men sexy is because anthropologically it’s about his resources. And now that we’re seeing women, older women as sexy, it’s a redistribution of power … because now they have resources too.”

Regardless of how viewers feel about reality stars who refuse to grow up, there’s a good reason why they keep tuning in.

“You watch these shows to feel two things: connection or disconnection. In that disconnection, you want to feel that you’re better than them. That’s the reason. It makes you feel better about you. And the other reason is they connect with the person. They see a little bit of themselves,” Dr. Nicolino explained.