What happens to healthy children in the first 12 months of life?

The first 12 months of your child's life are marked by so many learning experiences and developmental steps that they cannot all be listed in detail; it would take too long. We have summarized the most important points.

Please bear in mind that each child develops at their own pace and that development is very diverse from child to child.

Social behaviour

At approximately 6-8 weeks, the social smile appears for the first time. What is a social smile? The baby reacts to a familiar face with a smile. Initially, the smile is triggered by the contours of the human face. At this stage, a balloon can also cause a smile. But in the following weeks, the child increasingly focuses attention on the eyes and eyebrows. From the fifth month, the mouth starts to play a role and from the 6th month the child starts to pay attention and react to facial expression. Familiar people and strangers are distinguished by voice, appearance, and physical touch. This explains why children at this age can be shy.

Towards the end of the first year of life, the child begins to imitate simple actions such as clapping hands and waving.


At first, children sleep a lot and usually lie on their backs. But at the age of 3-4 months the child begins to turn on their side. Soon the child rolls over from back to stomach and back again. Sitting with support develops into free sitting at 4-6 months. The movements become more fluid and the child begins to crawl. Some children shuffle along on their buttocks. An important milestone in development is pulling to stand up and the first steps, until free walking begins on average at 12-14 months. Some children walk at the age of 10 months, others at 18 months.


Exploration of the world begins immediately after birth. First, the child explores things by putting them in their mouth. Then things are examined with the hands and finally, at the age of 8-9 months, things are specifically observed and examined.


Although no words are usually spoken in the first year of life, many preparatory steps take place. First, single sounds become sound sequences like bah-bah-bah, which finally change into mama-mama. Finally, the family choir is one strong voice richer!


But what about meals? The first teeth appear in most children between the fifth and eighth months. By the end of the first year of life at the latest, the range of foods has become much richer. Your child will have no trouble holding their own at the family table. In the meantime, they eat solid food and begin chewing. However, they also like to play with it; you might need to turn a blind eye to some of this.


In the beginning, the child sleeps a lot, and mostly without a regular day–night rhythm. At about 2 months, children begin to sleep more at night than during the day and a rhythm of two or three sleep episodes develops. The need for sleep is very different at every age and from child to child. Each child can only sleep as long as they need to. During daytime sleep, as much sleep as necessary is required to ensure that the child is active and satisfied when awake.


Remo H. Largo: Babyjahre. Die frühkindliche Entwicklung aus biologischer Sicht. Carlsen, Hamburg 1993. Piper, München 2010
Oskar Jenni und Remo Largo (2013): Wachstum und Entwicklung. In: Hoffmann, Lentze, Spranger, Zepp.
Pädiatrie: Grundlagen und Praxis, 4. Auflage. Seiten 8-91.