You've been watching her in a way you didn't watch the others. At seven months, you're keeping a quiet count: how often she looks up when you say her name, whether her smile reaches you across the room, what her hands do when she's excited. You haven't said anything out loud yet, because saying it would make it more real. The thought you keep having, the one you wouldn't share at the playgroup, is whether something is different about her. The first thing to know is that paying close attention is not catastrophizing. The earlier a parent notices the small things, the earlier a real evaluation can happen, and early intervention is one of the few areas in autism care where the timing genuinely changes outcomes [1].
Recognizing Early Signs
Detecting the early signs of autism in babies and kids matters because it sets up everything that comes next: pediatrician conversations, screening referrals, and the first conversations about therapy. This section outlines the signs that show up in the first months of life and by age two.
Signs in Infants and Newborns (0 to 3 months)
In the first three months, some behaviors can hint at later autism spectrum disorder (ASD). These include limited eye contact, a lack of social smiling, and delayed motor development [2]. Babies who later develop ASD often begin making less eye contact at around two months of age, which can be one of the earliest observable differences [3].
To be clear, no single sign in this age range is a diagnosis or anything close to one. Many infants who show one of these behaviors develop on a typical trajectory. What matters is the pattern, and whether the pattern continues or grows as the baby gets older.
In our practice, parents who notice something at this stage are often the ones who got an earlier diagnosis later on, not because the early sign was definitive, but because they were already paying attention by the time the more obvious differences emerged.
Signs by Age 2
By age two, the picture often becomes clearer. Most parents who eventually receive an autism diagnosis for their child first noticed something by this age. Common signs include limited eye contact, lack of gesturing (pointing, waving, reaching), and not responding consistently when their name is called [4].
Recognizing these signs early is important because it shortens the time between "something feels off" and "we have a plan." The longer that gap stretches, the more developmental ground a child can lose before a structured program starts.
Behavioral Indicators
When watching for early signs of autism in babies and kids, social interaction and communication are the two clearest windows. Behavioral indicators in these areas can flag potential developmental differences, including ASD.
Social Interaction Signs
Children with autism often find it harder to participate in everyday social back-and-forth. That can show up as difficulty making eye contact, not sharing focus with caregivers, or missing the small social cues most babies pick up around nine months of age.
The core feature of autism is a combination of challenges with social communication and interaction, paired with restricted or repetitive behaviors and interests. The presentation varies widely. Some children show clear differences from a young age; others don't show much until later, especially if they have strong language or cognitive skills that mask the social piece for a while.
Social interaction signs to watch for include:
- Limited or inconsistent eye contact
- Not following what others are focused on
- Not responding when their name is called
- Limited interest in other children
- Not sharing enjoyment, interests, or achievements with people around them
Communication Red Flags
Communication delays are another important indicator of ASD. Children with autism may have trouble with nonverbal communication skills like pointing things out or copying the sounds and gestures of others, which are typically expected from around nine months of age [5].
Delays in language development matter as well. Not saying one to three single words by age one can be a sign of ASD. A meaningful portion of children with autism remain minimally verbal into early childhood, with current research estimating roughly 25 to 30 percent [6].
Communication red flags to watch for include:
- Delayed speech and language skills
- Repetitive use of language (echolalia)
- Difficulty starting or continuing a back-and-forth conversation
- Trouble understanding what a listener already knows or wants
- Limited spontaneous or pretend play
If a parent or caregiver notices these signs, the next step is a professional evaluation, not a watchful-waiting period.
Read more about:What are Autism Meltdowns?
Developmental Milestones
Recognizing early signs of autism in babies and kids also involves watching how they meet or miss developmental milestones. The three areas that matter most are motor skills, language development, and sensory responses.
Motor Skills Delay
Children on the autism spectrum may show delays in motor skills, both gross motor skills (crawling, walking, jumping) and fine motor skills (grasping, using utensils, holding a pencil).
Signs can appear early. Some children have trouble learning to crawl or walk. Others walk on their toes, struggle with buttons, or have a hard time holding a crayon at the age peers do.
Nonverbal communication is also part of the motor skills picture. Pointing, waving, and copying gestures are expected from around nine months of age, and a consistent absence of those skills is one of the earlier developmental signals.
Language Regression
About 25 percent of children later diagnosed with autism spectrum disorder experience a regression in language and social skills between 15 and 24 months of age [5]. The regression can be sudden or gradual, and it usually shows up as a loss of words the child had been using and an increase in social withdrawal.
Even children who don't regress often use language in unusual ways. Some children label objects without using the word to ask for them. Others echo or repeat phrases they have heard, sometimes long after hearing them. A toddler who sounds like they're quoting a cartoon, rather than asking for juice, is often using language in a way that flags a developmental difference.
Sensory Challenges
Many children with autism have sensory challenges. They may be overly sensitive to lights, sounds, smells, tastes, or textures, or they may not respond at all to sensory input that would typically grab another child's attention. A toddler who shrieks at a hand dryer in a public bathroom, or who barely flinches when something falls behind them, is showing the kind of sensory pattern that often appears in early signs.
These sensory differences can affect daily life. A child may resist certain clothes, refuse foods of a particular texture, or struggle to focus in busy or noisy rooms. The result is often the kind of family workaround that's invisible to outsiders but exhausting to the parents living it.
Understanding these developmental milestones, and being aware of potential delays or regressions, helps parents and caregivers recognize early signs. Early detection sets up the kind of structured support that, in our experience, behavior cusps (small skills that unlock broader development) can be reached during the most learning-rich years of a child's life.
Screening and Diagnosis
Identifying the early signs of autism in babies and kids is one part of the picture. Translating those signs into a plan, a screening referral, a formal evaluation, and the right intervention is the other.
Early Intervention Importance and Seeking Professional Help
Recognizing the early signs of autism matters because it sets up the earliest possible start to therapy. Earlier evaluations lead to earlier services, and earlier services tend to produce stronger gains in communication, social skills, and adaptive behavior [1].
Known risk factors for autism include preterm or early-term birth, genetic factors, and certain environmental influences. There is no established link between vaccines and autism [2].
The American Academy of Pediatrics (AAP) recommends that autism screening be part of the standard 18-month and 24-month well-child visits. The Centers for Disease Control and Prevention recommends general developmental screening at 9, 18, and 30 months, with autism-specific screening at 18 and 24 months [4].
If a parent notices possible signs of autism in their baby or toddler, the practical first step is to schedule a visit with the child's pediatrician for evaluation. Parents and caregivers should observe how their child plays, learns, speaks, acts, and moves, and bring specific examples (not just general worry) to the appointment. A pediatrician can then refer to a developmental specialist, a developmental pediatrician, a child psychologist, or a neurologist for a full evaluation.
In our practice, the parents who get the fastest support are the ones who arrive at the pediatrician's office with concrete observations: dates, video clips, examples of what the child does and doesn't do. That kind of specificity moves a referral forward faster than general concern does.
Diagnostic Tools Overview
Only a qualified specialist can make an official diagnosis of autism, typically using the criteria described in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) published by the American Psychiatric Association.
Screening tools like the M-CHAT-R/F (Modified Checklist for Autism in Toddlers, Revised, with Follow-up) are commonly used in pediatric offices to identify children who may benefit from a more in-depth evaluation [6]. The M-CHAT is short, parent-completed, and designed to flag concerns rather than make a diagnosis on its own.
| Diagnostic Tool | Description |
| DSM-5 | Provides the criteria a clinician uses to diagnose autism |
| M-CHAT-R/F | A brief parent questionnaire used to flag children who need a fuller evaluation |
| ADOS-2 | A standardized observational assessment used by specialists to confirm a diagnosis |
ASD prevalence in the United States has risen over the past two decades, partly because of broader diagnostic criteria and better screening. According to the CDC's most recent surveillance data, about 1 in 36 eight-year-olds in the United States is identified with ASD [4]. That rising rate is one of the reasons screening at well-child visits has become standard.
Intervention Strategies
Once a diagnosis is in place, or even before it is formalized, intervention can begin. Early intensive behavioral intervention (EIBI), particularly when started before age three, is associated with meaningful gains in communication, social skills, and adaptive behavior [7].
In our practice, those first months of therapy are often built around small, foundational skills: responding to your name, looking up when a parent speaks, requesting a desired item using a sound, word, or sign, tolerating a non-preferred activity for short periods. A technique called errorless learning in ABA is often used in this stage, because it sets up the child to succeed on each trial rather than to fail and guess. The goal at this age is not to teach a long list of behaviors; it is to teach the child that learning with another person is rewarding.
Autism is a lifelong difference, not something to be cured. What changes with early therapy is the day-to-day picture: how a child communicates, plays, learns, and connects, and how a family functions around those skills.
Age-Specific Observations
Beyond the broad screening windows, certain signs become more obvious at particular ages. Watching for age-specific patterns helps parents and pediatricians know when to refer for evaluation.
Signs in Toddlers
Toddlers (typically ages one to three) explore the world through play, language, and movement. Some patterns within that exploration suggest a potential autism spectrum disorder.
Most children on the autism spectrum show delays in nonverbal communication and spoken language. They may label objects without using the word to ask for things. They may echo phrases for an extended period, or speak in a way that sounds more like adult speech than typical toddler speech.
Joint attention, the back-and-forth of sharing focus on the same object with another person, is also commonly delayed. A toddler who rarely looks up at a parent to share excitement about a passing dog, or who doesn't follow a parent's pointing finger to a new toy, is showing one of the more reliable early signs.
Signs in Preschoolers
In preschoolers (typically ages three to five), early signs of autism often show up in social play and conversational language.
A preschooler on the spectrum may not engage in pretend play by 18 to 24 months, may strongly prefer to play alone, and may speak with an unusual rhythm or in a flat monotone. They may give answers that don't quite match the question, or seem not to hear requests at all.
The core picture, challenges with social communication and interaction alongside restricted or repetitive behaviors and interests, often becomes clearer as social demands grow more complex [8]. Preschool is where the diagnostic picture sharpens for many children, because the social environment finally pushes hard enough that the differences become visible.
In both toddlers and preschoolers, none of these signs confirms an autism diagnosis, but each one warrants a closer look. The next step is a conversation with a pediatrician and, where appropriate, a referral for a developmental evaluation.
Why Mastermind Behavior
Mastermind Behavior is a BCBA-owned and operated in-home ABA therapy provider serving families across New Jersey, Georgia, and North Carolina. When parents call us about early signs of autism, they usually start the same way: "I'm probably overreacting, but..." We take those calls seriously, because the small things you noticed first are often the right things, and our BCBAs are trained to translate a parent's instinct into a structured assessment. From there, our Behavior Technicians run the daily, play-based therapy sessions in your home, working on the specific skills your child is still building: shared attention, gestures, first words, the back-and-forth of social play. Parent training coaches stay in close contact with you between sessions, so the strategies we're using in therapy show up in the diaper changes, the meals, and the bedtime routine where so much of early learning actually happens. With a 90%+ staff retention rate and no onboarding waitlist, most families start in-home ABA therapy within six weeks of the initial assessment.
If you've been quietly tracking signs in your baby or toddler and you're not sure what to do next, schedule a free consultation or call us at 732.507.9883. We'll listen to what you've noticed, talk through where a formal evaluation fits in, and help you figure out what early support could look like for your family.
References
[1] Centers for Disease Control and Prevention. "Treatment and Intervention Services for Autism Spectrum Disorder." https://www.cdc.gov/ncbddd/autism/treatment.html
[2] American Academy of Pediatrics, HealthyChildren.org. "Early Signs of Autism Spectrum Disorders." https://www.healthychildren.org/English/health-issues/conditions/Autism/Pages/Early-Signs-of-Autism-Spectrum-Disorders.aspx
[3] National Institute of Mental Health. "Autism Spectrum Disorder." https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd
[4] Centers for Disease Control and Prevention. "Data & Statistics on Autism Spectrum Disorder." https://www.cdc.gov/ncbddd/autism/data.html
[5] Autism Speaks. "Signs of Autism." https://www.autismspeaks.org/signs-autism
[6] Robins, D. L., et al. "Validation of the Modified Checklist for Autism in Toddlers, Revised With Follow-up (M-CHAT-R/F)." Pediatrics. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10951453/
[7] Reichow, B., et al. "Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders." Cochrane Database of Systematic Reviews. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870497/
[8] American Psychiatric Association. "What Is Autism Spectrum Disorder?" https://www.psychiatry.org/patients-families/autism/what-is-autism-spectrum-disorder
