SOME girls go through a teenage “mean girl” phase — but a psychologist has explained why Kylie Jenner and Hailey Bieber may not have grown out of it.

Kylie, 25, and Hailey, 26, are currently being accused of publicly bullying Selena Gomez, and the doctor says there are some “developmental issues” behind their “very immature” behavior.

Kylie Jenner, 25, and Hailey Bieber, 26, are currently being accused of publicly bullying Selena Gomez
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Kylie Jenner, 25, and Hailey Bieber, 26, are currently being accused of publicly bullying Selena GomezCredit: Instagram

Though Selena and Hailey were snapped together last year, fans are convinced Hailey is taking digs at her on social media
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Though Selena and Hailey were snapped together last year, fans are convinced Hailey is taking digs at her on social mediaCredit: Tyrell Hampton
Fans have long been aware of some bad blood between Selena and Hailey, dating back to the days of their love triangle with Justin Bieber.

The “Boyfriend” singer and his missus first got together during one of his off-again phases with Selena.

And just a few months after “Jelena” split for good, Justin was engaged to Hailey.

So fans really took notice early this year when Hailey appeared to take a dig at Selena in a TikTok with Kendall Jenner.

In a now-deleted post, Kendall, Hailey, and their friend Justine Skye lip-synced to an audio clip that said: “I’m not saying she deserved it, but I’m saying God’s timing is always right.”

Then last week, Hailey and Kylie seemed to mock Selena — and her “accidentally over-laminated eyebrows.”

Posting her own laminated brows shortly afterward, Kylie wrote: “This was an accident????” in an apparent mockery of the star.

She followed up with an all-eyebrows FaceTime screenshot with Hailey.

But if they thought fans would be laughing with them, they miscalculated. Social media users seem largely put off by their behavior, with many saying they’re behaving like catty teens.

Dr. Jenn Mann, author of The Relationship Fix, thinks they may have never grown up and are displaying stunted emotional development.

“It’s very immature,” she told The U.S. Sun.

“It does have a very ‘mean girl’ high school quality to it.

“But these are women who have millions of dollars and have successful careers and are grown-a** adults.

Last week, Selena posted a selfie and wrote that she 'accidentally laminated' her brows 'too much'
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Last week, Selena posted a selfie and wrote that she ‘accidentally laminated’ her brows ‘too much’Credit: Instagram/@selenagomez
“I think sometimes, certain people, male or female, get a little developmentally stunted.”

Though it can be due to trauma, “sometimes it happens because they made so much money at a young age and everyone around them just yesses them, so they’re not required to learn social decency.

“When you are so well known, you’re so famous at such an early age, you are less likely to have people say, ‘Hey, that’s inappropriate.’ Like, ‘Hey, don’t do that.’

‘You can kind of get away with more. Nobody stops you. So you don’t tend to end up learning some of these social decencies that one learns as an adult.

Soon after, Kylie posted a picture with her own laminated brows and a comment about it being an accident
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Soon after, Kylie posted a picture with her own laminated brows and a comment about it being an accidentCredit: Instagram/ kyliejenner

She followed it up with a FaceTime screenshot zoomed in on her and Kylie's brows
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She followed it up with a FaceTime screenshot zoomed in on her and Kylie’s browsCredit: Instagram
“But it really is a developmental issue to be stunted at a teenage-like age, and doing these kinds of teenage behaviors.”

Of course, Selena also got rich and famous at a young age — but unlike Hailey and Kylie, she didn’t grow up with famous family members who may have also been used to getting away with inappropriate behavior.

“I do think [if] you are surrounded by other people who don’t have to follow some of these social decency rules, that you’re more likely to be vulnerable to this kind of behavior,” said Dr. Jenn.

“You might be seeing this modeled by others in your family or in your social circle. And so you might think it’s okay.”

Fans think a video Hailey posted earlier this year was also meant to bully Selena
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Fans think a video Hailey posted earlier this year was also meant to bully SelenaCredit: TikTok / Riristea
Hailey hasn’t confirmed that she holds any negative feelings toward Selena, but their relationships with Justin overlapped — and that may have left her with some lingering resentment.

“Based on interviews that Justin did, it seems like when he came into the relationship and the marriage with Hailey, he was not totally resolved with his history with Selena,” said Dr. Jenn.

“And sometimes when that is the case, this other person can harm your relationship, and it can create some resentment.”

But it’s one thing to air that resentment privately with a BFF and a totally different matter to do it publicly on social media — especially to Kylie’s 379 million Instagram followers.

“I do think that that crosses a line,” said Dr. Jenn.

Hailey's relationship with her husband Justin Bieber overlapped with his relationship with Selena
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Hailey’s relationship with her husband Justin Bieber overlapped with his relationship with SelenaCredit: Getty
“I think that it’s very understandable to sit and talk with your girlfriends about someone you don’t like or someone your husband or boyfriend or girlfriend once dated.

“But to post publicly, especially when you’re a high-profile celebrity, it’s just it’s beneath their position.”

In this case, Dr. Jenn thinks Hailey and Kylie may have gotten caught up in a “catty headspace” and acted too “impulsively,” not realizing their antics could backfire.

“It might have kind of flashed through her mind, like, ‘Oh, my fans will support me,'” she said.

Instead, social media users have largely come to Selena’s defense, with some claiming that Hailey and Kylie are losing followers over the drama.

“You gotta hope that they will reevaluate their behavior, especially given the public outcry over it,” said Dr. Jenn.

“Unfortunately, they may reevaluate it in terms of monetary loss as opposed to moral or ethical standards.”

A psychologist said Hailey and Kylie appear to be developmentally stunted
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A psychologist said Hailey and Kylie appear to be developmentally stuntedCredit: AFP