At what age does a child typically achieve the milestone of sitting without support?

Explanation

## Gross Motor Milestones in Infancy **Key Point:** Sitting without support is a major gross motor milestone achieved between **6–8 months of age**. This marks the transition from supported sitting (4–6 months) to independent balance. ### Sequential Development of Sitting | Age (months) | Milestone | | --- | --- | | 3–4 | Head control in sitting, needs trunk support | | 4–6 | Sits with hand support (tripod sitting) | | **6–8** | **Sits without support (unsupported sitting)** | | 8–10 | Sits and pivots, reaches forward without loss of balance | **High-Yield:** The progression from supported to unsupported sitting reflects maturation of: - Core trunk stability (rectus abdominis, obliques, erector spinae) - Postural reflexes (righting and equilibrium reactions) - Cerebellar coordination **Clinical Pearl:** Delayed sitting (beyond 9 months) warrants evaluation for: - Hypotonia (cerebral palsy, Down syndrome, metabolic disorders) - Hypertonia (spastic cerebral palsy) - Developmental dysplasia of hip (DDH) **Mnemonic: SITS** — **S**ix to **I**ndependent **T**runk **S**upport (6–8 months). ### Contextual Milestones at 6–8 Months - Rolls both ways (prone to supine, supine to prone) - Transfers objects hand-to-hand - Raking grasp evolving to radial grasp - Babbling ("ba-ba", "da-da")