Baby Development Month by Month: What to Expect in the First Year

Milestone lists are useful for knowing roughly what's coming next — they are not an exam your baby needs to pass on schedule. The NHS describes development in ranges for exactly this reason: a "normal" age to sit unsupported spans several months, and healthy babies fall all across it.

What happens at 0–3 months?

• Physical: lifts head briefly during tummy time by 6–8 weeks; follows a face or bright object with their eyes; hands start to unclench and find their way to the mouth.
• Communication: the first real social smile usually appears between 6–8 weeks — often the moment that changes how parenthood feels.
• Sleep: no real day/night pattern yet; feeding on demand, day and night, is normal and expected.
• NHS check: the 6–8 week review with your GP or health visitor covers growth, hip and heart checks, and your own postnatal recovery — a good moment to raise any worries, however small.

What happens at 4–6 months?

• Physical: rolling front-to-back typically comes first, back-to-front follows; reaching for and grasping toys; bearing some weight on legs when held standing.
• Communication: babbling strings of sounds, laughing out loud, turning toward voices and sounds.
• Feeding: the NHS recommends starting solid food (weaning) at around 6 months — see our weaning guide for full readiness signs and first foods. Don't start before 4 months.
• Sleep: many babies begin longer overnight stretches, though plenty don't — both are within the normal range at this stage.

What happens at 7–9 months?

• Physical: sitting unsupported, then commando-crawling or classic hands-and-knees crawling (some babies skip crawling entirely and go straight to standing — also normal).
• Communication: understands simple words like "no" and their own name; babbling starts to sound more speech-like ("mama", "dada" as sounds, not yet meaningfully directed).
• Feeding: moving from purées toward mashed and soft finger foods, and starting to self-feed with fingers.
• A highchair becomes essential once independent sitting is established — see our best highchairs guide for what actually matters versus marketing.

What happens at 10–12 months?

• Physical: pulling to stand on furniture, "cruising" sideways holding on, and some babies take unsupported first steps by 12 months (the average is closer to 12–14 months, so don't worry if yours hasn't yet).
• Communication: first meaningful word (used consistently for the same thing) often appears around 12 months; understanding is well ahead of speaking at this age.
• NHS check: the 1-year review checks growth, hearing, vision and development, and is the point most health visitors formally discuss moving toward a varied family diet and stopping bottles in favour of a cup.

When should you seek advice sooner about development?

Contact your health visitor or GP if your baby isn't smiling by around 3 months, showing no interest in reaching for objects by 6 months, or isn't sitting with some support by 9 months — but remember these are prompts to ask, not signs anything is necessarily wrong. Trust your own instinct if something feels off; you know your baby best.

Two development threads worth their own deep-dives: vision has one of the clearest milestone sequences of all — our baby eye health guide covers tracking, squints and the warning signs, with EyeHealthGuide for the optical detail behind them.