3 month old baby

What a 3 month old baby is doing

Three months is when head control stops being a struggle. The HSE describes a baby who has good control of their head when seated, rests on their forearms while lying on their tummy, uses their hands to bat at objects, has hands loose rather than fisted most of the time, and can follow an object moving in a circular pattern with their eyes. They can also look at an object about an inch across held in front of them.

Communication moves on too. Your baby will chuckle, and will echo sounds made by someone talking to them. Their cries start to vary depending on what they are trying to say — hunger sounds different from pain. Expect warm smiles and laughter in response to your smiling, chatting and singing, crying when upset with a look for comfort, and settling to a calm voice.

Two things get searched hard at three months: rolling over and sitting up. Neither is a three-month expectation. The HSE places rolling front to back at around four months and rolling back to front at around six, and sitting with support at six months. A baby pushing back and stiffening in your lap is practising, not behind. The HSE also says plainly that its milestone ages are averages and that every child is different.

The 12 week vaccinations

On the current UK schedule, twelve weeks brings the second dose of the 6-in-1, the second dose of MenB and the second dose of the rotavirus vaccine. The paracetamol advice applies again at this appointment, because fever is common when MenB is given with the others.

Rotavirus is the one with a deadline. It is given as drops by mouth in two doses, at eight weeks and twelve weeks, and the NHS states that a missed first dose can still be given up to 15 weeks old and a missed second dose up to 24 weeks old. If your baby was unwell and missed an appointment, that is the window to work inside; contact your GP surgery. The NHS also advises waiting until a baby is feeling better before vaccinating if they have a high temperature, diarrhoea or vomiting.

Schedules differ by country and now, in the UK, by date of birth for the later doses, so check the schedule published where you live rather than a chart from elsewhere.

3 month old sleep: what the NHS actually says

Three months is the start of the NHS's three to six month band, and its wording is careful: by this stage your baby needs fewer night feeds so may be able to sleep for longer, and "some babies may sleep for 8 hours or longer at night, but not all will". That is the whole published claim. There is no official nap count, no bedtime, and no wake window figure from any national health body.

The NHS frames the whole first year the same way: as your baby grows their sleep pattern will change, and it can feel as though every time you have settled into a routine it changes again. Our wake windows guide sets out where the widely circulated awake-time charts come from and how much weight they deserve, which is less than the internet implies.

How much milk does a 3 month old need?

Same answer as at one and two months, and it is not evasion. No NHS page publishes a per-age volume, because the instruction is to feed responsively and let your baby decide when a feed is done. Wet nappies, soft poos and weight gain are the checks. Our baby feeding amount calculator shows the commonly used estimation methods and where each of them came from, rather than presenting one figure as official.

Why solid food still waits

Searches for three-month food charts and for baby rice in a bottle are common, and the NHS answer is unambiguous: introducing solid foods should start when your baby is around six months old. Waiting gives your baby time to develop so they can cope with solids — including purées, cereals and baby rice added to milk — and breast milk or first infant formula provides the energy and nutrients they need until then.

The NHS also names the behaviours parents mistake for readiness — chewing fists, waking in the night more than usual, and wanting extra milk feeds — and says these are normal baby behaviours, not necessarily a sign of hunger or readiness. It adds the line worth repeating: starting solid foods will not make your baby sleep through the night. Sometimes a little extra milk helps until they are actually ready.

What is worth raising

The HSE lists three specific prompts to contact a GP or public health nurse at three months: a baby who does not smile in response to others, who cannot hold their head up, or who cannot push their chest up when on their tummy. As always, losing a skill they previously had is worth a call whatever their age.

When to get urgent help

The fever threshold changes this month as your baby passes three months. The NHS says to call 111 if a baby aged three to six months has a temperature of 39C or higher, or if you think they have a high temperature; under three months the threshold is still 38C. Call sooner regardless of the number if your baby has other signs of illness such as a rash, is feeding much less than usual, has far fewer wet nappies, is difficult to wake, or their breathing looks like hard work.