Which milestones matter?
Broadly, most babies smile socially by around two months, sit without support by around eight months, and walk between twelve and eighteen months. Most say single words by around twelve to fifteen months and join two words by around two years. There is a wide normal range around each of these.
The pattern across all areas matters more than any single milestone. Delay in one area with everything else on track is assessed differently from delay across motor, speech and social development together.
When should I stop waiting?
Seek assessment if a child is not sitting by nine months, not walking by eighteen months, has no words by eighteen months, is not joining words by two and a half years, does not respond to their name, or shows no interest in interacting with familiar people.
Loss of a skill the child previously had, at any age, always needs prompt assessment rather than watchful waiting.
What causes developmental delay?
Causes range widely: hearing loss, prematurity, genetic conditions, brain injury around birth, seizures, nutritional deficiency including iron, limited stimulation, and conditions such as autism. In some children no single cause is identified, which does not prevent effective support from being planned.
What happens after assessment?
Assessment leads to a specific plan, which may include a hearing test, therapy referrals, blood tests where indicated, and a review appointment to track the trajectory. Progress between visits often clarifies the picture as much as any single test.
The five areas of development
Development is usually considered across five strands: gross motor skills such as sitting, walking and climbing; fine motor skills such as grasping, transferring objects and later holding a pencil; speech and language, covering both what a child understands and what they say; cognitive skills, meaning problem-solving, memory and play; and social and emotional development, including attachment, sharing attention and managing feelings.
Separating them matters because the shape of the delay points towards the cause. Isolated motor delay with everything else on track suggests something quite different from delay in language and social interaction together, or from delay across all five areas at once. When a parent says their child is behind, the first task is to establish behind in what.
Correcting for prematurity
A baby born early should be assessed against their corrected age, not the date on the birth certificate. Subtract the weeks of prematurity from their actual age: a nine-month-old born three months early is developmentally a six-month-old, and should be sitting like a six-month-old.
Correction is usually applied until around two years of age, by which point most children born preterm have caught up. This single adjustment resolves a great deal of unnecessary worry, and conversely prevents a genuine delay in a preterm child being dismissed as merely catching up when the gap is wider than prematurity explains.
Which tests are useful, and which are not
Investigation is directed by what the history and examination suggest, rather than run as a standard panel. A hearing test is close to universal where speech is affected, because hearing loss is common, easily missed and treatable. Vision is checked where visual behaviour seems unusual.
Blood tests may look for thyroid dysfunction, iron deficiency, vitamin D deficiency or rickets, all of which are worth finding because all are treatable. Genetic testing, most often a chromosomal microarray, is considered where there is delay across several areas, unusual facial or physical features, a family history, or where a specific condition is suspected. Brain imaging has a role when the examination is abnormal, the head size is unusual, or skills have been lost, but a scan ordered simply because a child is late to walk rarely changes anything and may require sedation.
Early intervention, and why timing matters
The developing brain is most adaptable in the first few years, which is the practical reason for not waiting to see. Early intervention typically combines physiotherapy, occupational therapy, speech and language therapy, and structured play, matched to the areas identified.
What determines progress most, however, is what happens at home between sessions. A therapy hour a week matters far less than the daily routines it shapes, and good therapists spend a portion of each session teaching the parent rather than only working with the child. If you leave a session unclear about what to do until the next one, ask, because that is the part that carries the work.
When the milestone charts do not fit
Charts describe averages, and healthy children vary considerably around them. Some skills have a genuinely wide normal range: walking anywhere between twelve and eighteen months is unremarkable, and a small number of normal children bottom-shuffle instead of crawling and walk later still.
What warrants attention is less a single late milestone than a pattern: delay across several areas at once, a widening gap over time rather than steady progress at a slower pace, loss of an established skill, or a marked asymmetry such as consistently using one hand before the first birthday. A single late milestone in a child progressing steadily elsewhere is usually a variation. A child who is slowly falling further behind is not, and that distinction is easier to see across two appointments than at one.
Frequently asked questions
Everyone tells me boys talk late. Should I wait?
Boys do talk slightly later on average, but this should not be used to dismiss a genuine delay. Assessment is quick, often reassuring, and identifies treatable causes such as hearing loss when they are present.
Will my child catch up?
Many children with isolated delay do catch up, particularly with support. The trajectory over the following months is a better guide than any single assessment, which is why review appointments are part of the plan.
Is delay the same as intellectual disability?
No. Delay describes where a child is now. Some children with delay catch up completely, some have a specific treatable cause, and some have a longer-term condition. Time and reassessment distinguish between these.
My child was born premature. Should I be measuring from the due date?
Yes. Use corrected age, subtracting the weeks of prematurity from their actual age, generally until about two years. A baby born two months early who is sitting at ten months is sitting at a corrected eight months, which is within the normal range. Most families are never told this, and it accounts for a great deal of avoidable worry in the first two years.
Everyone says my child will catch up. How do I know whether to push for assessment?
Reassurance from relatives is well meant but is not based on having examined the child. Assessment is quick and non-invasive, frequently ends in genuine reassurance, and where it does find something the finding is often treatable, such as hearing loss or iron deficiency. The cost of assessing a child who turns out to be fine is one appointment; the cost of waiting on a child who needed support is months of a period when intervention works best.
Does a diagnosis label my child for life?
Many parents hesitate for this reason. In practice a diagnosis is a key to support rather than a permanent verdict: it is what opens access to therapy, school accommodations and, where relevant, a disability certificate. Diagnoses given in early childhood are also revisited as children develop, and are revised when the picture changes. A child who is struggling without explanation tends to be labelled anyway, usually as lazy or naughty, which is the more damaging label of the two.
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Book an appointment
Consultations are by appointment at Huda, Sushant Lok 2, Sector 55, Gurugram. Tell us what is worrying you and the clinic will call you back.