What happens to healthy children at the age of 4 to 6 years?

Playing with friends, arguing with friends, experiencing limits, being brave, and being careful: At the age of four, lots of social skills develop that enable children to become engrossed in play together, to understand each other, and to imagine themselves in each other’s shoes. Many other aspects also develop, enabling children to go to kindergarten and school. For example, children develop their first ideas about time. They grasp concepts such as yesterday, today, and tomorrow, even if they don’t always have the patience to wait for tomorrow.

Social behaviour

By the age of four, most of the tantrums have passed. Previously, everything was only about them, but now your child is developing social feelings. They show empathy with others, which means that they care about their siblings and can put themselves in other people's shoes.

Your child begins to dress and undress independently. At least, they know pretty well what they want to wear today and what not.

Playing, drawing

Your child builds things like a house or an airplane out of Lego or toy bricks, and their first scribbling becomes lines and circles. People are drawn from head to toe, and the drawings become more and more detailed. Your child will draw situations, such as a mountain with a cable car.

Speaking

By the time they enter kindergarten, most children’s language has developed to the point that they can speak complete and grammatically correct sentences in daily life. Listen and show interest, even if the right words are on your tongue and talking about experiences sometimes gets a little confused.

Sleep

Now it is very clear that the need for sleep is very individual. The children sleep less during the day. So it is all the more important to keep the evening bedtimes constant and regular with rituals like reading a bedtime story.

Getting out of diapers

Most children learn to stay clean and dry with little effort from parents. Half of all children become clean and dry during the day in the third year of life. At the age of 5 years, most children are dry.

Source

Remo H. Largo: Kinderjahre. Die Individualität des Kindes als erzieherische Herausforderung. Piper, München 1999
Oskar Jenni und Remo Largo (2013): Wachstum und Entwicklung. In: Hoffmann, Lentze, Spranger, Zepp.
Pädiatrie: Grundlagen und Praxis, 4. Auflage. Seiten 8-91.