Neurodivergent Family Trees

neurodivergent family trees

Whether you have ADHD, autism, or a spicy blend of both, your neurodivergence likely does not exist in a bubble. For many with an adult diagnosis, there’s a phase of “Wow it’s so obvious, how did no one catch it?”. Shortly after that there’s usually an epiphany that the reason you went undiagnosed so long is because others in your family are also undiagnosed. From the new view of our neurodivergent perch, we look back at our family history and suddenly realize we come from some very neurodivergent family trees.

What is a Neurodivergent Family Tree?

To be honest, I’m not sure if this is an actual term or if I made it up. I use ‘neurodivergent family trees’ as a term to refer to the frequency in which autism, ADHD, and other forms of neurodivergence run in families.

From a personal anecdote, my ADHD wasn’t diagnosed until I was 31. The next time I visited my family I realized how wildly ADHD our household was. My step-dad and brother (technically my step-brother but we’ve never used the term for each other) both were diagnosed already so there were no surprises there. They have the typically male, external ADHD symptoms that so often earns them an earlier diagnosis. What was surprising was realizing how many of those “ADHD life hacks” you see on social media were things my step-dad had been doing for decades. Notes, lists, personal doom piles in dedicated spaces, and piles on the stairs were coping mechanisms we were unknowingly raised on.

I also suddenly understood why we so often had food items in multiples (because we thought we were out so we got more and then we forgot that we already got more.) The fridge of expired products suddenly made a lot of sense too. As did the forgotten-about gift cards that were often left to whither into expiry; sad and unused. I realized my mom definitely has undiagnosed ADHD and my [step] sister has since been diagnosed as AuDHD also. For those keeping count, that’s 5/5 for the household count. We also have some suspicions about various grandparents and other family members. I think the fact we’re a blended family adds an interesting touch. Instead of an intense example of the inheritably of neurodivergence, we’re just further proof of the neurodivergent tendency to cluster.

Are Neurospicy Family Trees Common?

Neurodivergent family trees are probably more common than most of us realize. There are generations of quirky family members with unusual habits and collections that were never diagnosed. Once you start seeing neurodivergent symptoms, they tend to become very obvious when you look back at your family members’ habits and interests.

Let’s look at some numbers. 1 in 36 children are diagnosed with autism. Current numbers claim 1 in 100 adults have autism. But you don’t grow out of being autistic so how can 1 in 36 children have it but only 1 in 100 adults? Additionally, research has found that 25% of autistic kids are not diagnosed by age 8. If they’re not diagnosed by that age, the more masking undiagnosed children learn which is to their detriment. Masking is exhausting and requires a level of severance between your needs and what others expect from you. It also can lead to other issues that can impact families for generations.

In terms of ADHD, as of 2020, 366 million adults globally are diagnosed. Current numbers in the US show about 2.3% of the population is diagnosed with ADHD. However, experts who have studied the underdiagnosis of ADHD (particularly in women) think closer to 5% of the US population lives with ADHD. That’s a lot of neurodivergent family trees that may not even know they are one.

What Does the Research Say?

So what does the research say? That I’m right, of course. Kidding. (Kind of.) Seriously though, a lot of autism research in the past focused on older siblings which has obvious limitations. However, in 2019 a more thorough study was conducted that looked at first- to fourth-degree relatives and the risk of autism spectrum disorder (ASD) with and without intellectual disability.

This study had a few notable findings:

  • Family history of mental and neurological disorders led to increased odds of ASD
  • 63% of people with ASD had a parent with a history of mental and/or neurological disorders
  • Family history of multiple disorders, including ASD, led to higher odds of ASD
  • The more closely related the affected family member is, the higher the odds of ASD
  • ASD without intellectual disability was associated with more disorders compared to ASD with intellectual disabilities
  • ASD with intellectual disabilities had weaker familial association with other mental disorders but stronger familial association to some neurological disorders compared to ASD without intellectual disability

Other researchers have estimated autism is 40-80% heritable. While the connection is clear, we still don’t fully understand the how and why. That’s because there are as many as 1,000 different genetic changes that may impact how brain cells communicate in people with autism.

ADHD Family Trees

ADHD is highly heritable with a rate of 70-80%. Of parents with ADHD, one-half to one-third will have a child who has ADHD. If a parent has ADHD, their child has a 50% chance of having it and if a child has ADHD, their siblings have a 30% chance of having it as well.

How Can This Information Help My Neurodivergent Family?

The more we understand about each other, the more empathetic we can be; enabling us to build stronger relationships. A diagnosis helps us understand ourselves better and gives us more words and tools to communicate our needs. Those are tools we can also use to understand neurodivergent family members better so we are operating from the right framework.

For many of us who were undiagnosed until adulthood, we’ve experienced a fair amount of trauma as a result. Not only are we accused of being overly dramatic, demanding, and self-centered, but many of us were raised by undiagnosed parents as well. To a child, an undiagnosed parent with ADHD is distracted and forgetful and can lead to internalized feelings of unimportance. An undiagnosed autistic parent can lead to a household with a lot of similarities to households with a narcissistic parent. This all leads to a lot of unresolved trauma and very different versions of reality between family members.

It’s easy to be resentful over those experiences (and that’s valid) but I’ve found it helpful to have the framework of the neurodivergent family tree. I understand my family better and it’s improved my interactions and thus, relationships as a whole with them.

I also realize how it could have helped things with previous generations. One of our grandpas was particularly quirky in a way I now easily recognize was the ’tism. He was pretty difficult in a variety of ways that I think would have made things easier for him and helped us navigate better had we had the correct framework. I wish we had resources like this guide for seniors with autism because it would have helped in so many ways.

Moving Forward for Healing

Sometimes it’s really easy to be angry. Angry over how we were treated and the trauma induced by the lack of a diagnosis. But that anger isn’t productive; it doesn’t make anything better. I could easily dwell on the unfair treatment and lack of support and resources but how does that help me now? It doesn’t. By having the framework of the neurodivergent family tree I better understand how I fell through the cracks. I now see that my parents were in the near-constant sensory-induced fight-or-flight mode that I struggle with. While my mom’s forgetfulness can still sting, I now have a better context for it and am finding ways to cope with it better. I’m writing this blog in hopes that this information can help you in similar ways.

What about you? Do you have a neurodivergent family tree? Did this blog give you a new perspective on your family and how you grew up? What’s your funniest “It’s wildly obvious now, how did we miss it?” moment?

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  1. temp mail

    Excellent website with a wealth of useful information; I am forwarding it to some acquaintances and also sharing it on Delicious. Many thanks for your hard work.

    1. AriC

      Thank you so much, your comment means so much to me!

  2. Notes by Dan

    I really really loved this post! I also was diagnosed with ADHD when I was already an adult, and retrospectively it is clear that ADHD is ever-so-prevalent in my family tree! Especially in ethnic families that “look down upon” these neurodevelopmental disorders, the number of neurodivergent diagnoses is far lower than it should be, had there been no stigma against seeking help or treatment for it. It’s interesting how the cultural context heavily affects and influences the statistics, as well as contributes to the stigmatization of neurodivergence!

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