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A Hidden Cause of Some Difficult Family Relationships

"I began to see the symptoms in my sister. She was undiagnosed and unsupported."

Key points

  • Researchers have identified many root causes of estrangement, but undiagnosed autism is not on that list.
  • The number of people diagnosed with autism has skyrocketed, as many are identified due to increased awareness.
  • Neurotypicals often suffer with a loss of a satisfying connection with an autistic relative and depression.

Research psychologists have identified many of the root causes of sibling estrangement. They include abuse, trauma, death of one or more parents, financial disputes, substance use disorders or mental health issues, political differences, and highly competitive relationships.

Yet some cutoffs don’t fall neatly into these common categories, leaving estranged siblings confused as to why they just can’t establish meaningful connections with a brother or sister. Anecdotal evidence points to a possible unidentified cause of distance and estrangement among siblings: an undiagnosed autism spectrum disorder (ASD).

A recent study of autism in adults estimates that 2.2 percent of American adults have an autism spectrum condition. The U.S. Centers for Disease Control and Prevention estimates that 5.4 million people age 18 and older, or about one in 45 people, have ASD. In recent years, the number of people diagnosed with autism has skyrocketed, as children and adults are more likely to be diagnosed due to increased awareness.

Adults with high-functioning autism, especially those having average or higher-than-average intelligence, are often diagnosed later in life. They were born before high-functioning autism was included in the diagnostic literature, and many people with autism have managed to mask or hide their autistic traits. Interestingly, parents sometimes discover that they themselves are “on the spectrum” after their child is diagnosed.

The mystery in one woman’s family

Recently, several readers have contacted me and identified this variable in their own difficult sibling relationships.

One woman shared her story:

My sister was emotionally unavailable and always pushing me away, and I could not make any meaningful connection with her. Her thinking was very black-and-white, and she was unable and unwilling to compromise. I felt lonely and rejected.

I had been a schoolteacher, working with autistic students. That’s when the penny dropped for me. I began to see the symptoms of autism in my sister. She was undiagnosed and unsupported.

We are English immigrants to Australia, so I didn’t have access to the other half of my family. Therefore, I had no familial reference points regarding autistic behaviors. In recent years, I discovered many cousins in the UK are diagnosed on the autistic spectrum. It’s taken me a lifetime to connect the dots. I’m proud of myself for pursuing this mystery in my family.

Another reader reports that she had never thought of autism as a factor in her brother’s distance and difficulty in relating to her. When her nephew was diagnosed with autism spectrum disorder, however, she saw her brother’s behavior reflected in her nephew’s symptoms.

“The distance in our relationship feels much less personal now,” she says. “I see that he simply is incapable of the kind of emotional connection I would like in a sibling. Now, I’m more able to accept him for who he is without expecting more.”

Identifying the problem

ASD is a developmental disorder that varies widely in its manifestations and severity. Generally, however, it causes a broad range of behavioral, communication, and social challenges. An individual with ASD may show only a few or many of these behavioral indicators:

  • Has difficulty relating socially and requests alone time
  • Seems emotionally distant
  • Has unusual sensory responses or preferences (sensitivity to light, noise, textures in fabric or food, etc.)
  • Is intensely interested in a few subjects, to the exclusion of others
  • Has trouble with focus and organization, especially for tasks that do not hold their interest
  • Has fixed daily routines; outbursts when changes occur
  • Has trouble with change and transitions
  • Has difficulty processing emotionally laden communication and becomes overwhelmed
  • Has trouble interpreting facial expressions, body language, or social cues
  • May struggle with knowledge and or expression of their own inner world and others’ emotion
  • Struggles to see themselves as a part of a family unit or household
  • Has difficulty relating to their own children and or addressing their needs
  • Has difficulty regulating emotion
  • “Lectures” instead of engaging in reciprocal conversation
  • Struggles with symptoms of mental health or neurodevelopmental issues, including but not limited to anxiety, depression, ADHD or learning delays or disabilities

The Neurotypical Sibling Experience

The stressors in the family, when one child has ASD, are palpable. Often, the first clue for the neurotypical sibling—people who have brains that function in a similar way to most of their peers—is his or her sense of isolation. Several studies show that neurotypical siblings of those who have ASD often feel lonely and depressed. Some feel sad and frustrated about the lack of reciprocity in their sibling relationship, and they have a sense of loss about their limited connection with a brother or sister.

As with many disorders and illnesses, family life seems to revolve around the one person who has ASD, even if theirs is a mild case. This breeds resentment in neurotypical siblings who receive (or feel they receive) less parental time and attention than the child with ASD.

Some brothers and sisters may not have identified the root of their sibling's difficulties in childhood, but the situation becomes acute in adulthood when the neurotypical sibling realizes it’s simply impossible to sustain a meaningful relationship with a brother or sister who may have ASD. Clearly, this factor is worthy of serious consideration for distant or estranged siblings, and this topic could be fertile ground for research.

Facebook image: Olena Yakobchuk/Shutterstock


Sipowicz, Kasper, Frontiers in Psychology, 05 August 2022 Being an adult sibling of an individual with autism spectrum disorder may be a predictor of loneliness and depression – Preliminary findings from a cross-sectional study Sec. Pediatric Psychology, Volume 13 - 2022 |

Holl, Emily, Autism Spectrum News (October 1, 2020) Siblings: Common Concerns and Effective Support Strategies

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