How does baby development happen?
Baby development in the first 12 months is amazing. Through warm and responsive interactions with you and other caregivers, as well as play, babies learn to communicate, think, move, express emotions and much more.
Development is progressive, with each change building on earlier ones. And development happens in a similar order in most babies, but skills might develop at different ages or times. For example, babies usually learn to sit up, and then they learn to crawl. But this development can happen at any time between 4 and 10 months.
If you’re wondering whether your baby’s development is on track, just remember that development happens over time. Differences among babies are usually nothing to worry about. But you know your baby best. If you feel that something isn’t quite right, it’s important to talk to your child and family health nurse or GP. It’s also OK to get another opinion if you’re still concerned.
What are baby developmental milestones?
Developmental milestones are behavioural or physical signs of a baby’s development. Developmental milestones are a useful guide for tracking your baby’s development.
Developmental milestones are grouped under headings according to the parts of the body they refer to:
- Large body movements (gross motor skills) involve the coordination and control of large muscles and include skills like walking, sitting and running.
- Small body movements (fine motor skills) involve the coordination and control of small muscles and include skills like holding a rattle and picking up crumbs.
- Vision is the ability to see near and far and to understand what you see.
- Hearing is the ability to hear, listen to and understand sounds.
- Speech and language is the ability to make and understand sounds that form words.
- Social behaviour and understanding is the ability to learn and interact with others. It includes skills for play, connecting and communicating.
For month-by-month information about what happens in the stages of baby development, check out our newborn development trackers and our baby development trackers.
What causes delays in baby development?
Many things can cause babies to develop more slowly than others. Developmental delay can be short or long term.
Causes of short-term delay include physical illness, long periods in hospital and family stress.
Longer-term developmental delay might happen because of genetic conditions or because of complications during pregnancy and birth, like premature birth or fetal alcohol spectrum disorder.
Getting early support for development is important. Sometimes children who get early support need less or no support as they get older.
When to seek help for baby development
If you’re seeing delays in a few different areas or if your baby shows signs of losing skills they once had, it’s best to seek advice early from a child health professional. See your child and family health nurse, GP or paediatrician.
Here are signs that your baby might need support for their development.
Physical signs
Your baby:
- doesn’t seem to see things or hear properly
- can’t use both arms or legs
- can’t hold their head up by the time they’re 3-4 months old
- can’t sit up on their own by 9 months
- isn’t crawling by 12 months
- isn’t bearing weight on their legs by 12 months.
Behaviour signs
Your baby:
- has an unusual cry – for example, a high-pitched squeal
- is persistently crying for more than 3 hours in total a day, especially after 3-4 months.
Note that it’s natural for babies to cry for about 2 hours in total a day, with crying peaking at 6-8 weeks.
Social, emotional and communication signs
Your baby:
- doesn’t look at you
- isn’t interested in what’s going on around them
- doesn’t consistently respond to sounds
- isn’t babbling by 6 months.