🍼 Age-based baby guide

Week 12: Many babies now feel like tiny comedians in training – they beam at you, coo and squeak in reply, swat at toys, stare in wonder at their own hands, and then suddenly switch back to cuddle-and-sleep mode when their busy brain has had enough.

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Key points

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Around twelve weeks, lots of babies have a few brighter awake windows where they calmly take everything in, watch faces and simple toys, and turn towards familiar voices or a nearby light.
Social smiles are often easier to see now, and many babies “talk back” with coos, soft vowel sounds, and little squeals when you smile, chat, or sing, as if they are practising their side of a conversation.
Feeding usually still takes up a large part of the day, but some parents notice that their baby drinks in a smoother rhythm, sometimes finishes a feed a bit faster, and may have slightly longer pauses between some feeds.
Movements often look stronger and more deliberate, with many babies waving their arms and legs with more control, bringing their hands together, or trying to bat at a nearby toy.
Sleep is still commonly spread across day and night in several chunks; some families start to see one or two longer stretches, while other naps and nights are still very changeable from day to day.
Playtime often feels more fun and interactive now, with babies enjoying peekaboo-style games, simple songs on repeat, and the discovery that their own fingers are a very interesting built-in toy.

Feeding

Guide

At around week 12 many babies still feed often both day and night, and responsive feeding – offering breast or bottle when they stir, root, or suck their hands – usually continues to fit well with their small stomach and steady growth.
Some parents notice feeds feel more settled now, with their baby latching more quickly, sucking and swallowing in a regular pattern, and relaxing their fists, shoulders, and face as their tummy fills and they feel satisfied.
Regular wet nappies, soft poos, and routine weight checks with a midwife, health visitor, or paediatrician are often looked at together to see how feeding is going over time, alongside how alert and content the baby seems after most feeds.

Sleep

Guide

At twelve weeks many babies still sleep for a large part of each 24 hours, usually in lots of shorter stretches, and it is common for nights to include several wakes for feeds, warmth, or reassurance, even if one stretch may start to feel a little longer.
Parents are often advised to place their baby on their back in a clear, flat sleep space in the same room as an adult, keeping pillows, duvets, and soft toys away from the baby’s face and keeping the room smoke-free to support safer sleep.
Many families keep daytime naps in normal light and everyday sounds, and make night-time care calm, low-light, and fairly brief, which can gently help babies link bright, chatty times with day and quieter, snuggly times with night, without using strict schedules.

Pee and Pooping

Guide

By this stage many babies have a familiar rhythm of wet nappies and soft poos that might be mustard yellow, brown, or slightly green, and loud squirts or very serious “poo faces” are still everyday sights in many homes.
Some babies poo several times a day, while others poo less often but in larger amounts, and parents usually know their baby’s usual pattern well and can spot changes – such as suddenly going a lot more or a lot less – quite quickly.
If wet or dirty nappies suddenly become very rare, or if you notice very pale poo, blood, or other changes that worry you, you are encouraged to contact your midwife, health visitor, paediatrician or local emergency service.

Learning

Guide

Around week 12 many babies are practising early communication skills, such as holding eye contact for a little longer, smiling in response to your smile, and making soft coos or squeaks when you talk, which all help them learn that you are someone who answers their signals.
A few times a day, for a few minutes when your baby is calm and awake, you might sing a favourite song, repeat a simple rhyme, or slowly move a high-contrast toy or your face from side to side so they can follow with their eyes, then pause when they look away or start to fuss.
Short, watched bits of tummy time on your chest, across your lap, or on a firm surface help your baby practise lifting and turning their head and using their arms, and weaving this in for a song or story’s length a few times a day gently builds strength for later rolling and sitting.

Sources

This content is general information only and is not medical advice. If you are worried about your baby, contact your midwife, health visitor, paediatrician, or local emergency service.