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The first year flies by like a sped-up film: today your baby can barely focus their eyes, and a few months later they’re waving “bye-bye”. Between those two points there are so many small and big discoveries that it’s easy to get lost in the lists. So we’ve laid them out briefly here – as a map, not an exam.
The important bit, right at the start: every baby has their own timetable. The stages below are signposts, not deadlines.
The short answer: Around 2 months: most babies smile back. 3–4 months: cooing and soft chuckles. 5–6 months: laughing and rolling from tummy to back. 7–9 months: sitting without support. 10–12 months: pulling up to stand and waving bye-bye. If your baby loses a skill they already had, talk to your paediatrician.
What does “developmental milestone” actually mean?
A developmental milestone is a skill most children reach around a certain age – a smile, sitting up, a first word. In 2022 the US Centers for Disease Control and Prevention (CDC) updated their “Learn the Signs. Act Early.” checklists. They now list the skills that at least 75% of children already have by that age. Before, the benchmark was the “average” child – around 50%.
In other words: if your baby isn’t doing something on the exact day they turn that many months, it’s no reason to worry. The checklists exist to help parents and paediatricians spot early if something needs a bit more attention.
0–2 months: getting to know each other
- Calms down when you talk to them or pick them up.
- Around two months, most babies smile when you smile at them.
- Makes sounds other than crying.
- Lifts their head briefly when lying on their tummy.
3–4 months: cooing and first giggles
- Coos – those soft “aaah” and “oooh” sounds.
- Chuckles softly and smiles to get your attention.
- Holds their head steady when you’re holding them.
- Brings their hands to their mouth and grips a toy placed in their palm.
5–6 months: testing and trying
- Laughs out loud and blows raspberries.
- Takes turns with you in a “conversation” of sounds.
- Reaches for a toy they want.
- Rolls from tummy to back, and pushes up on straight arms when on their tummy.
You don’t need a special diary. When something delights or puzzles you, take a photo or jot a word in your phone with the date. At the next check-up you’ll have real examples instead of “I think it was last month…” 😊
7–9 months: sitting up and “ma-ma-ma”
- Sits without support and gets into a sitting position on their own.
- Babbles with repeated syllables like “ma-ma-ma” and “ba-ba-ba”.
- May be shy with strangers – a sign they now recognise their own people.
- Looks for a toy they’ve dropped.
- Moves objects from one hand to the other.
10–12 months: pulling up and a first “bye-bye”
- Pulls up to standing and cruises along holding on to furniture.
- Waves “bye-bye” and calls a parent “mama”, “dada” or another special name.
- Picks up small things between thumb and index finger – the so-called pincer grasp.
Independent steps usually come a little later – in the CDC checklists they’re a signpost between 15 and 18 months. If your baby sets off earlier – wonderful. If not – there’s time.
And crawling? In the updated checklists it’s no longer a separate milestone, because babies get moving in lots of different ways: some crawl, some shuffle along on their bottoms, and some go straight to standing.
For the dads
Many of these skills are best practised through play: pulling faces face to face, “conversations” made of sounds, chasing each other on all fours across the rug. If your style is louder and more physical – brilliant. Babies love variety.
Try the “echo”: when your baby says “ba”, say “ba” back and wait. That little pause is an invitation to keep the conversation going – and very often they accept it.
When should you talk to your paediatrician?
If your baby loses a skill they already had, or if something just keeps nagging at you, mention it to your paediatrician without waiting for the next scheduled check-up. You know your child best, and your question is always welcome. The CDC’s free checklists (there’s also a Milestone Tracker app) are a handy helper for that conversation.
In short
The first year isn’t a race against the clock. It’s a series of little “hey, look what I can do!” moments – each in its own time. You’re already doing the most important thing: watching, listening and being there. The rest will come with time. 💛
Sources: CDC – Milestones by 6 Months (Learn the Signs. Act Early.); CDC – Milestones in Action: By 1 Year; American Family Physician – CDC’s Revised Developmental Milestone Checklists; The Conversation – Babies almost all try crawling, but CDC says it’s not a useful milestone.
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