# Early Signs of Down Syndrome in an 18-to-24-Month-Old

Canonical: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-down-syndrome-in-a-18-to-24-month-old
Publisher: Pinnacle Blooms Network / Bharath Healthcare Laboratories Private Limited

By 18–24 months, Down syndrome is almost always already confirmed at birth, so this stage is about supporting development — watching gentler-paced movement, speech and learning, often with low muscle tone — and beginning early therapy, not searching for a diagnosis.

*By 18 months, Down syndrome is almost always already known — but this stage is when how your child grows and learns truly comes into focus, and gentle support makes a real difference.*

## In short
Down syndrome ([ICD-11 LD40.0](/down-syndrome)) is usually identified at or near birth through physical features and a confirming chromosome test, so at 18–24 months you are rarely *discovering* it — you are watching how your child develops. At this age you may notice slower-paced milestones in movement, speech and learning, often alongside low muscle tone (hypotonia). These are areas to support and monitor, never reasons for alarm.

## What you may notice at 18–24 months
**Movement and muscle tone**
- Low muscle tone — a softer, floppier feel; sitting, standing or walking arriving later than peers
- Greater flexibility in joints; tiring more easily during active play

**Communication and play**
- Fewer words than expected, or first words arriving later
- Understanding often ahead of spoken language — your child may follow more than they can say
- Learning new skills at a steadier, gentler pace

**Everyday skills and senses**
- Feeding or chewing taking more practice
- Recurrent ear infections or glue ear, which can affect hearing and speech
- Routine eye and hearing checks are especially important at this stage

## The science, simply
Many of these patterns trace to hypotonia and to the wider health picture that can accompany Down syndrome — which is exactly why paediatric guidelines recommend regular vision, hearing and thyroid checks, plus early developmental therapy. Speech, occupational and physiotherapy started early help your child build on real strengths: social warmth, visual learning and a love of routine. Progress is the goal, on your child's own timeline.

## The Pinnacle way
Developmental measurement supports care planning; diagnosis requires an appropriately qualified healthcare professional., under the care of qualified clinicians — never from an online list. Our team builds a strengths-first plan across [speech therapy](https://www.pinnacleblooms.org/top-speech-therapy-center-india-proven-improvement-rate) and [special education](/special-education), with progress tracked using the [AbilityScore®](/ask/what-is-the-abilityscore-and-how-is-it-calculated), a clinician-administered structured assessment. Across 70+ centres and 25 million+ therapy sessions, we walk this path alongside families every day.

## Trusted sources
Aligned with WHO ICD-11 (LD40.0), CDC "Learn the Signs. Act Early." developmental milestones, the Indian Academy of Pediatrics, and American Academy of Pediatrics guidance via HealthyChildren.org.

**Next step —** book a developmental check on WhatsApp at +91 91001 81181, and we will design a warm, early-support plan around your child's strengths.

This is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.

## Sources
- WHO ICD-11: https://icd.who.int/en
- CDC — Learn the Signs. Act Early.: https://www.cdc.gov/child-development
- American Academy of Pediatrics (HealthyChildren.org): https://www.healthychildren.org

## Connected topics and perspectives
- Conditions: https://pinnacleblooms.org/ask/conditions
- Parent / Family: https://pinnacleblooms.org/ask/lens/stakeholder/parent
- Toddler-18-24: https://pinnacleblooms.org/ask/lens/age/toddler-18-24
- Context: https://pinnacleblooms.org/ask/lens/domain/context
- Early Signs: https://pinnacleblooms.org/ask/lens/intent/early_signs
- Screen: https://pinnacleblooms.org/ask/lens/lifecycle/screen
- Special Education: https://pinnacleblooms.org/ask/lens/route/special-education
- Early Clarity: https://pinnacleblooms.org/ask/lens/empowerment/early_clarity
- Down Syndrome: https://pinnacleblooms.org/ask/lens/condition/down-syndrome
- English: https://pinnacleblooms.org/ask/lens/language/en
- SDG 10: Reduced Inequalities: https://pinnacleblooms.org/ask/lens/sdg/10
- SDG 3: Good Health and Well-being: https://pinnacleblooms.org/ask/lens/sdg/3
- SDG 4: Quality Education: https://pinnacleblooms.org/ask/lens/sdg/4
- ASHA / PHC / Frontline: https://pinnacleblooms.org/ask/lens/stakeholder/asha_phc
- Doctor / Pediatrician: https://pinnacleblooms.org/ask/lens/stakeholder/doctor
- Teacher / Educator: https://pinnacleblooms.org/ask/lens/stakeholder/teacher

## Related question paths

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- How Down Syndrome Affects a Child's Daily Life: https://pinnacleblooms.org/ask/how-does-down-syndrome-affect-a-child-s-daily-life
- Is Down Syndrome Considered a Disability?: https://pinnacleblooms.org/ask/is-down-syndrome-considered-a-disability
- Is Down Syndrome Genetic or Hereditary?: https://pinnacleblooms.org/ask/is-down-syndrome-genetic-or-hereditary
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- What is Down Syndrome, and what are its ICD-11 features in early childhood?: https://pinnacleblooms.org/ask/what-is-down-syndrome-and-what-are-its-icd-11-features-in-early-childhood
- ICD-11 Classification for Down Syndrome (LD40.0): https://pinnacleblooms.org/ask/what-is-the-icd-11-classification-for-down-syndrome
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### Recognise signs & concerns
- Early Signs of Down Syndrome at 12–18 Months: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-down-syndrome-in-a-12-to-18-month-old
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- Early Signs of Down Syndrome in a 3-Year-Old: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-down-syndrome-in-a-3-year-old
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- Down Syndrome in Girls: https://pinnacleblooms.org/ask/do-girls-show-down-syndrome-differently
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### Understand assessment
- How does AbilityScore track progress in a child with Down Syndrome?: https://pinnacleblooms.org/ask/how-does-abilityscore-track-progress-in-a-child-with-down-syndrome
- How Down Syndrome Is Assessed in a Young Child: https://pinnacleblooms.org/ask/how-is-down-syndrome-assessed-in-a-young-child
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- What does an AbilityScore of 100–200 mean for a child with Down Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-100-200-mean-for-a-child-with-down-syndrome
- What does an AbilityScore of 200–300 mean for a child with Down Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-200-300-mean-for-a-child-with-down-syndrome
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- What an AbilityScore of 400–500 Means for a Child with Down Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-400-500-mean-for-a-child-with-down-syndrome
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### Explore therapy & support
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- Down Syndrome AbilityScore 200-300: Next Steps for Parents: https://pinnacleblooms.org/ask/my-child-with-down-syndrome-has-an-abilityscore-of-200-300-what-should-we-do-next
- Down Syndrome: AbilityScore 300–400 — What To Do Next: https://pinnacleblooms.org/ask/my-child-with-down-syndrome-has-an-abilityscore-of-300-400-what-should-we-do-next
- Down Syndrome & an AbilityScore of 400–500: What to Do Next: https://pinnacleblooms.org/ask/my-child-with-down-syndrome-has-an-abilityscore-of-400-500-what-should-we-do-next
- Down Syndrome: AbilityScore 500–600 — What to Do Next: https://pinnacleblooms.org/ask/my-child-with-down-syndrome-has-an-abilityscore-of-500-600-what-should-we-do-next
- Down Syndrome & an AbilityScore of 600–700: what to do next: https://pinnacleblooms.org/ask/my-child-with-down-syndrome-has-an-abilityscore-of-600-700-what-should-we-do-next