What are the signs of autism in toddlers?

Learning the early signs of autism can be helpful for parents and caregivers to ensure children get the earliest intervention possible if a professional evaluation is needed.

Each child is unique, and not all may show every sign of autism. However, many autistic children may show some of the traits discussed and spotting the signs early can ensure that, if they need extra support, this can be accessed as soon as possible. It’s also important to note that toddlers without autism may still exhibit some of these behaviours, so seeing any of these behaviours in isolation isn’t necessarily indicative of autism.

Table of contents

• Signs of autism in young children
• How autism may look in children at different ages
• Autism in toddlers: the difference between girls and boys
• What should you do if your toddler shows signs of autism
• How can you support an autistic toddler
• Next steps towards an autism diagnosis

Signs of autism in young children

Signs of autism in toddlers can include behaviours such as not responding to their name being called, avoiding eye contact, and being upset by certain smells or tastes. Below are some of the main signs of autism in toddlers:

Avoiding eye contact

Some autistic children may avoid making eye contact or may find it uncomfortable. This can be one of the early signs that they experience the world differently and may not respond in ways typically expected.

Not responding to their name

Autistic children might not always respond to their name. This isn’t due to a lack of hearing or understanding, but how they process and interact with the world around them.

Not smiling when being smiled at

A young autistic child might not smile back when others smile at them. This could indicate challenges in social engagement and communication. These are common traits in autism.

Being upset by sensory triggers

Autistic children may have heightened or reduced sensitivity to sensory experiences. Triggers can include loud noises, bright lights, or certain textures. This sensitivity can cause them to become upset or distressed in situations that might not bother other children. It may also cause them to seek out certain sensory input more than other children.

Other signs

• Repetitive movements
• Repetitive phrases
• Being quiet to a degree that is unexpected for their age group
• Finding it more difficult to pretend play

Learn more in our full guide to the symptoms of autism.

How autism may look in children at different ages

Although autism in toddlers presents itself in a number of ways, it may present itself differently as children grow older:

Six months

At this age, some signs of autism may include limited or no big smiles or other warm, engaging expressions. A child might also show reduced or absent eye contact, which can be an early indicator of differences in social interaction.

Nine months

By nine months, an autistic child may show little or no back-and-forth sharing of sounds, smiles, or other facial expressions. This lack of reciprocal interaction is a key developmental milestone that may be delayed.

12-24 months

As children grow, the signs of autism may become more noticeable.

• By 12 months, there may be little or no babbling and a lack of back-and-forth gestures like pointing, showing, reaching, or waving. Additionally, children might show little or no response when their name is called.
• By 24 months, there might be few or no meaningful two-word phrases, excluding imitations or repetitions. These signs can indicate potential developmental delays in communication and social skills.

Autism in toddlers: the difference between girls and boys

Autism presents itself differently between young girls and boys. Here are some of the ways that autism can differ:

Girls

• Autism in girls may be more challenging to recognise in early years.
• Girls might develop coping mechanisms that mask social difficulties.
• They may appear more socially engaged, despite underlying struggles.
• Intense focus on specific interests may be mistaken for typical behaviour.
• Girls are often more adept at imitating social behaviours, potentially delaying diagnosis.

Boys

• Autism in boys is often more apparent and may be recognised earlier than in girls.
• Boys are more likely to show traditional signs, such as communication challenges and repetitive behaviours.
• Social interaction difficulties in boys are typically more pronounced and noticeable.
• Boys may engage in repetitive play or have a strong preference for routines, making their differences more evident.

What should you do if your toddler shows signs of autism

If your toddler shows signs of autism, you should schedule an appointment with your GP or healthcare provider.

Learn more about how autism-friendly support can help your child.

How can you support an autistic toddler

There are a number of ways that you can support your child, before or after they’ve had their autism diagnosis.

These methods can be used for day-to-day support, or as long-term strategies to help in your child’s development:

• Create predictable routines.
• Use clear and simple communication.
• Be patient and compassionate.
• Seek professional support.
• Create a sensory-friendly environment.
• Connect with support groups.

Next steps towards an autism diagnosis

Learn about autism and discuss assessment options by taking the first step. While we don’t offer assessments to children under five, our triage team will be equipped to offer you guidance on how to proceed.

Contact us now at 0203 326 9160.

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