It means struggling with guilt that we may have done better and anger that we are left alone. It is taking up the disrupted threads of our lives and finding new patterns to weave of them. It is giving up a person who is no more. This is the problem that children have. While they are little, children do not believe that a life can not exist.
Children know little about time.
Children do not understand forever. Many believe that dying is reversible and that the dead can come back to life. Until they are quite sure a person is no more and will never be, they can not finish the work of mourning. If children can not finish mourning, they can not free themselves to go on with life and love and growing. Only through adult honesty and support can a small child work through death in ways which will help him grow.