Children follow a sequential pattern in their physical and mental development, but the pace of progress varies for each individual.
For children with Down syndrome, developmental milestones are typically achieved at a slower rate than in typically developing children. The table below provides a reference for comparing the developmental milestones of typically developing children with those of children with Down syndrome.
For children with Down syndrome, developmental milestones are typically achieved at a slower rate than in typically developing children. The table below provides a reference for comparing the developmental milestones of typically developing children with those of children with Down syndrome.
| Gross Motor Skills (Locomotion) | ||
| Developmental Milestone | Age Range (Typically Developing Children) | Age Range (Children with Down Syndrome) |
| Holding head steady when picked up | 1–4 months | 3–9 months (average 5 months) |
| Rolling over independently | 2–10 months | 4–12 months (average 8 months) |
| Sitting up independently without support | 5–9 months | 6–16 months (average 9 months) |
| Standing independently without support | 5–9 months | 12–38 months (average 18 months) |
| Walking independently without support | 9–17 months | 13–48 months (average 23 months) |
| Walking up stairs with assistance | 12–24 months | 20–48 months (average 30 months) |
| Walking down stairs with assistance | 13–24 months | 24 months–5+years (average 36 months) |
| Running | Around 2 years | Around 4 years |
| Riding a tricycle | Around 3 years | Around 5 years |
| Fine Motor Skills (Hand-Eye Coordination) | ||
| Developmental Milestone | Age Range (Typically Developing Children) | Age Range (Children with Down Syndrome) |
| Tracking objects with their eyes | 1–3 months | 1.5–6 months (average 3 months) |
| Reaching for and grasping a rattle | 2–6 months | 4–11 months (average 6 months) |
| Transferring objects between hands | 4–8 months | 6–12 months (average 8 months) |
| Stacking two blocks (approx. 2.5 cm each) | 10–19 months | 14–32 months (average 20 months) |
| Imitating drawing a circle | 24–40 months | 36–60 months |
| Communication Skills | ||
| Developmental Milestone | Age Range (Typically Developing Children) | Age Range (Children with Down Syndrome) |
| Turning head toward the sound of speech | 2–6 months | 3–8 months (average 6 months) |
| Babbling with repetitive sounds (e.g., "ba-ba ma-ma") | 5–14 months | 7–18 months (average 11 months) |
| Responding to familiar words | 5–14 months | 10–18 months (average 13 months) |
| Saying the first meaningful word | 10–23 months | 13–36 months (average 18 months) |
| Using gestures to express needs | 11–19 months | 14–30 months (average 22 months) |
| Forming two-word phrases | 15–32 months | 18 months–5+years (average 30 months) |
| Social and Self-Care Skills | ||
| Developmental Milestone | Age Range (Typically Developing Children) | Age Range (Children with Down Syndrome) |
| Smiling in response to interaction | 1–2 months | 1.5–4 months (average 2 months) |
| Recognizing mother or father | 1–5 months | 3–6 months (average 3.5 months) |
| Feeding themselves a cookie | 4–10 months | 6–14 months (average 10 months) |
| Drinking from a cup | 9–17 months | 12–30 months (average 20 months) |
| Staying dry during the day without diapers | 14–36 months | 18 months–4+years (average 36 months) |
| Controlling bowel and bladder functions | 16–48 months | 20 months–5+years (average 36 months) |
| Dressing and undressing without buttons | Around 3 years | Around 4–5 years |
