Tallulah Willis is opening up for the first time about being diagnosed with autism as an adult.
The 30-year-old daughter of Bruce Willis and Demi Moore revealed the diagnosis on Instagram last week and shared a video of herself as a child touching her dad's head while he was being interviewed.
"Tell me your autistic without telling me your[sic] autistic," Willis captioned the video.
In response to a commenter asking when she was diagnosed with autism, Willis said it was a recent revelation.
"Actually this is the first time I've ever publicly shared my diagnosis," she wrote. "Found out this summer and it's changed my life."
In addition to her autism diagnosis, Willis has previously shared publicly that she was diagnosed with ADHD as a teenager and, in 2022, was diagnosed with borderline personality disorder, a "mental illness that severely impacts a person's ability to manage their emotions," according to the National Institute of Mental Health.
In now sharing her autism diagnosis publicly, Willis has placed a spotlight on the fact that people of all ages can be diagnosed with autism, not just children.
Autism was not added to the Diagnostic and Statistical Manual of Mental Disorders (DSM), the manual used to diagnose mental disorders, until the early 1980s, and at the time, it was only classified as a disorder impacting children.
For people like Willis who were not diagnosed with autism as children, behaviors they notice in adulthood may reveal a diagnosis after consultation and evaluation with a mental health provider such as a neuropsychologist, psychologist, or psychiatrist.
In the video she shared on Instagram, Willis claimed in the comments that she was "stimming," a type of repetitive behavior that is not exclusive to but common in kids and adults who have autism.
Autism, also known as autism spectrum disorder, is a developmental disability that impacts over 5.4 million adults and nearly one in 44 children in the United States, according to the Centers for Disease Control and Prevention.
Autism is defined by the CDC as a "developmental disability that can cause significant social, communication and behavioral challenges."
People with autism have a wide variety of traits affecting communication, behavior and socialization, according to the CDC. The "spectrum" in autism spectrum disorder means that there's a wide range of symptoms and severity.
In children, autism spectrum disorder can be identified as early as infancy, although most children are diagnosed after the age of 2.
MORE: Mom of kids with autism on why she doesn't stop their stimming or 'hide their happy'Signs of autism may include deficits in social communication and interaction like not making eye contact, not showing an interest in or difficulty making friendships and "inflexible adherence" to certain routines or topics of interest, according to the CDC. Additional signs of autism spectrum disorder may include delayed social interactions, exhibiting repetitive behaviors or showing a limited interest in activities and sensory issues like sensitivity to noise or sound.
There is no medical test to diagnose autism spectrum disorder, so doctors watch a child's behavior and development to make a diagnosis, according to the CDC. Formal evaluations by a neuropsychologist, psychologist, or psychiatrist are also needed to make the diagnosis.
MORE: Tallulah Willis opens up about Borderline Personality Disorder diagnosis and dad Bruce WillisThe American Academy of Pediatrics now recommends all children be formally screened for autism spectrum disorder at their 18- and 24-month-old well-child visits.
With a diagnosis, treatment for autism comes in many different forms, from mental health therapy to occupational, physical and speech therapies.
Sometimes medications can be helpful for things related to ASD, like mood problems or inability to focus.
Because much of the diagnosis of autism is focused on children, adults who are interested in being assessed for autism should look for a neuropsychologist or other mental health provider who is certified to assess adult patients.
