Early Red Flags of Autism in Toddlers: What Parents and Caregivers Should Know

Early childhood is a period of rapid social, emotional, and cognitive development. While children develop at different rates, certain developmental patterns may signal the need for closer monitoring or professional assessment. Autism Spectrum Disorder (ASD) is a neurodevelopmental condition that typically emerges in early childhood, and research consistently shows that early identification and intervention are associated with better long-term outcomes.

This article outlines common early red flags of autism in toddlers (generally between 12 and 36 months), intending to support awareness—not diagnosis.

Understanding Autism in Early Childhood

Autism Spectrum Disorder is characterised by persistent differences in social communication and interaction, alongside restricted, repetitive patterns of behaviour, interests, or activities. These characteristics exist along a spectrum and can vary widely in presentation and severity.

In toddlers, signs of autism may be subtle and are often related to how a child engages socially, communicates, and responds to their environment.

Key Red Flags to Look For

1. Differences in Social Engagement

Toddlers typically show a strong interest in people. Potential red flags may include:

• Limited or inconsistent eye contact

• Rarely responding to their name by 12 months

• Limited interest in social games (e.g., peek-a-boo)

• Appearing content to play alone most of the time

• Reduced sharing of enjoyment, such as smiling or showing toys to others

A lack of social reciprocity—going back and forth socially—is often one of the earliest indicators.

2. Delays or Differences in Communication

Communication differences may involve both verbal and non-verbal behaviours:

• Delayed speech development or absence of spoken words by 16 months

• Loss of previously acquired words or babbling

• Limited use of gestures (e.g., pointing, waving, nodding)

• Using a caregiver’s hand as a tool rather than communicating needs directly

• Echolalia (repeating words or phrases without clear communicative intent)

Importantly, some toddlers may have strong vocabulary skills but still show difficulties with functional or social use of language.

3. Limited Joint Attention

Joint attention refers to the ability to share focus on an object or event with another person. Red flags may include:

• Not pointing to show interest or draw attention

• Not following another person’s point or gaze

• Difficulty sharing interest in objects or experiences

Joint attention is a foundational skill for social and language development and is often reduced in autistic toddlers.

4. Repetitive Behaviours and Restricted Interests

Repetitive or inflexible behaviours may include:

• Repetitive hand movements (e.g., flapping, finger flicking)

• Spinning wheels, lining up toys, or focusing on parts of objects

• Strong distress with changes in routine or environment

• Highly specific or intense interests unusual for age

While repetition is developmentally typical to some degree, the frequency, intensity, and rigidity of these behaviours are key considerations.

5. Sensory Sensitivities or Differences

Many autistic toddlers experience sensory processing differences, such as:

• Over-reactivity to sounds, textures, lights, or smells

• Under-reactivity to pain or temperature

• Seeking sensory input (e.g., spinning, crashing, mouthing objects)

• Strong aversions to certain clothing, foods, or grooming activities

Sensory differences can significantly affect daily functioning and emotional regulation.

When to Seek Professional Support

If a toddler is showing multiple red flags or developmental regression (loss of previously acquired skills), it is recommended to seek a developmental screening or assessment. Professionals who commonly assess early development include:

• Clinical or developmental psychologists

• Paediatricians

• Speech-language pathologists

• Occupational therapists

Early intervention services do not require a definitive diagnosis in many regions and can begin as soon as developmental concerns are identified.

A Strength-Based Perspective

It is important to approach autism through a balanced, strength-based lens. Autistic children often demonstrate unique strengths, such as strong visual skills, attention to detail, honesty, creativity, and deep interests. Early identification is not about labelling, but about understanding a child’s needs and supporting their development in an informed and compassionate way.