What do children know about death? What thoughts surround their minds when faced with such a sad universe? How do they feel when they lose their parents, relatives or loved ones to death? And what do we know about the union of these two very different universes: childhood and death? Currently, the rates of urban violence, the emergence of diseases and the occurrence of natural phenomena have been responsible for a considerable number of deaths, of which the existence of children who are victims of the physical loss of their parents or loved ones is inevitable. This context led us to research the process of understanding death and children's mourning experience, in order to understand how they elaborate/introject this concept and how they experience the stages of physical mourning. Thus, we describe this evolution according to chronological age, outlining these processes and identifying the psychological aspects inherent in the context, in order to subsidise work with bereaved children and their families, providing them with elements that help them understand and identify the moment their child is going through, thus guaranteeing them adequate psychological care and support.