Children don’t start thinking immediately after birth. After a child is born, he starts undergoing different stages of development. These changes take place according to the age of a child. They are known as the cognitive developmental stages. Developments take place in a child’s brain as well as in the physical body. Babies only focus on what they see in their immediate environment.
At age 7, babies enter the pre-operational stage, that allows them to think reasonably. Here, children develop imaginations, can keep their memories, along with having the ability to differentiate between the past and the present. Although children cannot grasp complex information, understanding the basics is easy. Children only think about themselves because their understanding is based on their emotions. Concrete operational stage enables them to realize that there are other external events, that is, things that do not involve them also happen. Children also begin to understand that feelings are personal and cannot be shared by anyone else. Adolescents fall in the last category, where symbols are used to explain some events as well as to come up with possibilities to an event.
All this put into consideration, children get the ability to remember from age seven, when their brains have developed a little.