Early childhood is always the most important developmental period in human life. Young children not only grow physically during early childhood, but they also grow mentally. Children began to improve their skills in both observing and interacting with the world around them from an early age. They also make enormous improvements in information processing, conceptual resources, perceptual ability, and language learning. As children continue to grow, they understand how the world changes with age and experience. This child is reaching a certain stage of cognitive development, which focuses on mental processes such as perceiving, remembering, believing and reasoning. The most significant theory in the field of cognitive development is by Jean Piaget. Piaget was born in Switzerland and was a biologist, philosopher and behavioral scientist. He proposed that children around the world proceed through a series of four stages in a fixed order, which are sensorimotor, preoperational, concrete. This stage begins from birth until about the age of two. During this period, children are busy discovering the relationships between their body and the environment. However, the child's knowledge of the world is limited to sensory perceptions and motor activities. They understand the world mainly by touching, sucking, chewing and manipulating objects. At the end of this phase some symbolic skills such as the use of language and images develop. According to Piaget, the development of object permanence is one of the most important achievements in the sensorimotor stage of development. Object permanence is the child's understanding that objects continue to exist even when he is not allowed to see them or. For example, if the mother puts a toy under a blanket, the child will be able to look for it easily. This proved that the child achieved the goal