Your baby's growth and development - 4 months old

At 4 months old, your baby is becoming stronger, more social and more curious. Their head control is improving and many babies start trying to roll.

Your baby is due to have their scheduled vaccinations at 4 months old. Babies who are Aboriginal and/or Torres Strait Islander may be offered an additional vaccine.

At 4 months old, your baby is growing steadily, but usually not as fast as in the early weeks.

Every baby grows at their own pace. Some babies grow a little faster, while others grow more slowly.

Your baby's weight and length will be checked at regular health checks. These measurements are compared with standard growth charts to make sure your baby is growing steadily.

While every baby develops at their own pace, there are things that babies and children are generally expected to be doing at each age. These are called 'milestones'.

Physical development

At 4 months old, your baby is getting stronger and more active. They may wriggle, wave their arms and kick their legs up and down.

During tummy time, your baby may push up on their forearms and lift their chest. When gently pulled to sit, they can usually hold their head up with little support.

Your baby may start trying to roll. Never leave your baby alone on a change table or on any raised surface. Read more about how to prevent your baby from falling.

Your baby may also:

• reach for toys
• grab dangling objects
• hold items placed in their hands, such as a rattle

Your baby may put things in their mouth to explore. This is common and helps them learn new skills, as well as prepare for solid food. Make sure small objects are kept out of reach to avoid choking.

Cognitive development

Your baby is becoming more curious about their surroundings. They may enjoy:

• looking around
• watching people and activities
• focusing on faces and objects

Your baby learns through their senses, such as sight, sound and touch. They may repeat actions as part of learning.

Social development

Many babies begin to show early preferences for familiar adults. Your baby may:

• smile
• laugh
• show excitement when interacting with you

They often make eye contact when held close and may turn their head toward the sound of voices. Back-and-forth interaction — when you and your baby take turns responding to each other's sounds, smiles and expressions — is an important part of social development at 4 months old.

Emotional development

Crying is still your baby's main way to show their needs. They may cry to tell you they are hungry, tired or need a nappy change. When you respond and soothe them, your baby may settle more easily.

Your baby may also show excitement when they see you prepare to feed them.

Language development

Your baby communicates before they start to use words. Crying is their main way to express needs. When they are calm and content, your baby may make small throaty noises like coos or gurgles.

As you talk to your baby, they may start to copy simple mouth or tongue movements. Some babies may also begin making early babbling sounds, such as 'ga ga'.

As your baby starts to settle into a daily routine, they are often awake more during the day.

This gives you more time to interact and bond with them.

You can support your baby's development by:

• playing with them
• letting them look at and touch objects with different colours, shapes, designs and textures
• reading, singing and talking to them — this helps their language development over time
• spending time looking at each other, smiling and responding to their sounds

Help your baby build neck strength with tummy time. This is when you place your baby on their tummy for short periods, adding up to at least 30 minutes across the day. As your baby gets stronger, they may enjoy longer periods on their tummy. Always stay with your baby during tummy time and place them on their back for sleep.

It's also a good idea to think about preparing your home for when they start moving around. Simple changes now can help keep them safe as they become more active.

Read more about how your baby learns and what you can do to support their development.

Talk to your doctor or maternal child health nurse if your baby:

• isn't feeding well
• cries a lot or is hard to settle
• isn't moving their arms or legs
• isn't responding when you play with them
• isn't making or responding to sounds
• isn't responding to familiar faces
• has sleeping patterns that worry you

At any age, it's important to speak to your doctor if your baby has stopped doing something they had already learned to do. This is sometimes called 'regression'.

Read more about common worries and fears for parents.

If you are worried or would like to discuss any issues with your baby's development, speak to your doctor or maternal child health nurse.

You can also reach out to these support groups:

• The Australian Children's Education and Care Quality Authority has information about your child's development from birth to 4 months old.
• The Australian Breastfeeding Association has information about weight gain and growth patterns in breastfed babies.
• Children's Health — Queensland Hospital and Health Service has a fact sheet on development skills and activities from birth to 4 months old.
• Tresillian has information on baby milestones and development.
• Child Health Info has a child development guide from birth up to 12 months old.