10 Subtle Signs of Autism in Young Children

By Tracy Tully, MS, CCC-SLP | September 2026

Marly is a bright, funny, affectionate five-year-old with an incredible memory. She learned her letters early and surprised everyone when she started reading, despite never really being taught. She loves other kids, talks a lot at home, plays pretend, makes eye contact, and can tell you more than you ever asked to know about ladybugs.

Nothing about Marly immediately fits the picture of autism her parents have in their heads. But there are little things they’ve wondered about. She reenacts the same scenes over and over. Open-ended questions are unexpectedly difficult. She notices details nobody else seems to see and has very specific ideas about how games should go. Over the years, people have called her shy, sensitive, dramatic, particular, a perfectionist, and a leader. 

Bennet is a quiet, energetic three-year-old who loves trains and trucks. He’s affectionate and playful and loves being chased, tickled, and swung through the air. He knows The Very Hungry Caterpillar by heart and can name more vehicles than most adults.

Nothing about Bennet immediately screams autism to his family either. But there are little things they’ve wondered about. He loves watching wheels spin at eye level and can spend a long time exploring toys in the same way. He knows lots of words but doesn’t always use them when he needs something, and sometimes repeats familiar phrases instead. When he’s deeply engaged, it can be surprisingly hard to get his attention. He’s been described as stubborn, independent, busy, and “just doing his own thing.” 

Autism spectrum disorder (ASD) is characterized by differences in social communication alongside restricted or repetitive patterns of behavior, interests, or activities. These characteristics are presents in early development but may become more noticeable as social and everyday demands increase. In speaking children with strong language or academic skills, the pattern can be particularly subtle.

As a licensed and certified Speech-Language Pathologist, I wanted to share 10 subtle characteristics that might indicate that a child would benefit from a developmental evaluation.

1. They repeat questions or familiar phrases

You ask, “How are you?” and hear, “How are you?” They may quote shows or use familiar phrases with the same wording and sing-song intonation.

Repeating words and phrases right away, or later on, can be a meaningful part of communication and language development. Gestalt language processing is a developing area of research exploring how some children may learn and use language in larger chunks.

2. They look at or play with things a little differently

They may play with toys in a repetitive or unusually inspective way that simply looks “particular” or “organized.” Maybe all the blocks need to face the same direction, or the dolls are carefully lined up in a special way. 

They might get down to eye level to watch wheels turn, look at objects from the corner of their eye, or become especially interested in reflections, shadows, lights, or movement. These patterns can reflect repetitive play, sensory interests, or visual exploration and may be subtle enough to blend into everyday play.

3. They REALLY love something

Garbage trucks. Elevators. Tornadoes. Maps. Dinosaurs. Ladybugs.

Sometimes an interest is noticeably deeper or more persistent than a typical favorite. Clinically, these may be called highly focused or restricted interests, and they can also be wonderful sources of joy, expertise, regulation, and connection.

4. Their pretend play follows a familiar script

A child may have a big imagination but prefer to play out the same stories, repeat characters’ exact lines, or want pretend play to unfold in a particular way. They may happily play on their own but have a harder time when another child joins in, changes the story, or has a different idea.

5. Their skills seem surprisingly uneven

A child might read years above their age but struggle to answer, “What did you do today?” They might memorize entire books but have difficulty following a new direction. More broadly, a child may have an uneven developmental profile, with advanced skills in some areas and greater support needs in others, such as potty training, self-feeding or asking for help. 

6. They talk a lot, but conversation is harder

A child may have a huge vocabulary, but back-and-forth conversation still feels different. You say, “You’ll never guess what I saw today!” and it hangs in the air. They may have great eye contact and engagement when talking about a favorite topic, but less when the topic shifts. They may rarely ask questions or seem to miss yours.

This back-and-forth connection is called social reciprocity and is a key part of social communication in autism.

7. Their attention seems inconsistent

“I know she hears me. I just can’t tell when she’s listening.”

A child might notice a tiny sound from another room but seemingly miss their name being called. Looking at attention, sensory processing, engagement, and context can tell us much more than assuming a child is simply ignoring us.

8. Small changes feel surprisingly big

The wrong cup. A different route. Someone sitting in their spot. A friend changing the rules.

What looks like “stubbornness” from the outside may involve cognitive flexibility, regulation, or a strong preference for predictability and sameness.

9. They have little repetitive habits you barely notice

They might suck their thumb, bite or pick at their nails, rub a favorite texture, quietly repeat a sound, twist something in their fingers, replay the same part of a video, or arrange belongings in a particular way. These small, repetitive habits may provide comfort, enjoyment, focus, or regulation and can be easy to overlook because they’re woven into everyday life.

10. They make friends easily but differently

They may love other kids but connect best through the kinds of play they naturally enjoy, like repeating the same game, running and crashing together, or bonding over a very specific interest. They may happily play alongside another child or focus more on the activity than on talking or interacting throughout it.

Do any of these describe your child?

At Tully Speech & Language, I partner with Dr. Colleen Corcoran, PhD, through the Developmental Assessment Collaborative to provide autism, ADHD, and developmental evaluations for children in Denver. We take the time to understand your child, the patterns you’ve been observing, and whether they are better understood under a diagnosis umbrella or are simply part of typical development.

Not sure whether an evaluation makes sense? Reach out and tell me a little about your child and what has you wondering. I’ll help you figure out the next steps.