Diagnosing personality disorders in children is controversial due to natural developmental shifts in mood and behavior. When maladaptive traits remain pervasive and persistent, however, a personality disorder may be present.

Personality disorders are long-standing patterns of maladaptive, inflexible traits and behaviors that stray significantly from what many accept as cultural norms. The traits in personality disorders remain stable and constant over time, and they cause impairment in major areas of function.

Healthcare professionals tend to accept that personality disorders don’t usually emerge until adolescence and early adulthood. Before these stages of life, your personality and sense of identity are in a state of flux and evolution.

These natural transitions in personality make the diagnosis of personality disorders in children extremely challenging — and extremely controversial.

Under current clinical guidelines in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR), doctors can diagnose personality disorders in children under the age of 18 years.

The only exception is for antisocial personality disorder, which has an age requirement of over 18 years.

The DSM-5-TR indicates that a personality disorder diagnosis in a child is unusual but that a doctor can give one if maladaptive personality traits are present for at least a year and are persistent, pervasive, and unrelated to a particular developmental stage or another mental health condition.

The controversy

Despite the allowance in the DSM-5-TR guidelines, the diagnosis of personality disorders in children is controversial.

“Diagnosing a personality disorder in a child is like trying to define a story that’s still unfolding, often becoming clearer in the later chapters of adolescence or early adulthood,” explains Marina Kerlow, a licensed marriage and family therapist in Takoma Park, Maryland.

She says that personality disorders are difficult to diagnose in children due to their ongoing personality development and the potential for symptoms to change over time.

The DSM-5-TR notes, for example, that children often display traits of personality disorders that naturally decline as they near early adulthood. These traits, like narcissism, are a part of developmental learning.

A 2019 longitudinal cohort study investigating personality disorder traits among third-, sixth-, and ninth-graders found that common traits associated with personality disorders naturally decreased among children over a 36-month period.

Despite these concerns about confusing development with a personality disorder, the lines remain blurry. Because personality disorders often emerge in adolescence — the stage of life that blends adulthood with childhood — some experts believe that early onset, or childhood, personality disorders are underrecognized.

Due to the controversy surrounding childhood personality disorders, research is limited, and the exact prevalence of these conditions isn’t known.

One 2023 large-scale Danish study of more than 115,000 children and adolescents found the most common personality disorders to be:

  1. borderline personality disorder (BPD)
  2. unspecified personality disorder
  3. schizotypal personality disorder

In the research, children under the age of 10 years made up 3–6% of those with personality disorder diagnoses. The majority of diagnoses were in participants 15 years and older.

Borderline personality disorder

BPD is classified as a cluster B personality disorder. It’s one of several conditions that share features of erratic, emotional, or dramatic behaviors.

BPD involves patterns of instability in relationships, mood, and self-image. It also features notable impulsiveness across multiple areas of life.

Recognizing a personality disorder in a child is challenging, even for trained professionals. Children are constantly learning, growing, and adapting. Their path of development may involve volatile emotions and impulsive behaviors that don’t necessarily indicate a personality disorder.

Kim Homan, a licensed marriage and family therapist from Nashville, Tennessee, says that one of the first possible signs of a personality disorder in a child is chronic, pervasive patterns of behavior that are markedly different from those of their peers.

“These can include extreme mood swings, intense and unstable relationships, persistent difficulties in school or with peers, impulsive behavior, and a marked inconsistency between their actions and societal expectations,” she says.

In addition, Homan explains that personality disorders can manifest differently in children than in adults due to their ongoing developmental process.

“For instance,” she says, “while an adult with a personality disorder may have long-term patterns of unstable relationships and self-image, a child may exhibit these patterns primarily in their interactions with family and peers.”

Symptoms of borderline personality disorder in a child

The diagnostic criteria for BPD are the same for children and adults. BPD typically causes symptoms such as:

  • an intense fear of abandonment
  • frequent feelings of emptiness
  • an aversion to being alone
  • emotional volatility and inappropriate anger
  • impulsivity
  • risky behavior
  • acts of self-harm
  • a distorted sense of self

These symptoms are largely based on adult experiences of BPD, however. Research on the symptoms of BPD in children is an emerging area of study.

According to a 2019 review, predictors of BPD at an early age may also include:

Doctors primarily treat personality disorders in children and adults with psychotherapy, also known as talk therapy. The most common frameworks include:

These therapies can help children restructure their unhelpful personality patterns while learning how to be mindful of their emotions and control their emotional reactivity.

Some children may also benefit from medications to help reduce distressing symptoms, such as worry or impulsivity.

Healthcare professionals can diagnose personality disorders in children, though many in the healthcare space consider this controversial. True personality disorders in children are rare.

Children are still developing, and many traits associated with personality disorders naturally improve with age.

When a child does live with a personality disorder, their behaviors often differ notably from those of their peers, and their traits are consistent and pervasive.

A mental health professional can give a personality disorder diagnosis to a child when maladaptive personality patterns are present for at least a year.