This article reports a retrospective comparative study of 10 mothers whose loss of a child caused chronic major depression despite medication followed by psychotherapy. The mothers were compared to 10 other mothers who participated in a longitudinal study conducted over the time period between the occurrence of the tragedy and complete recovery. The mothers were compared on the basis of life-event data, a semidirective interview, and a projective inquiry using the Rorschach Test. Some important differences were found between the two groups of mothers, from the standpoint of the support offered by their therapist, the elaboration of guilt feelings following the loss, their ability to mentally represent the trauma as assessed by the Rorschach Test, and their capacity to disinvest the lost object. Two factors that were not considered at the beginning of the research seem to fulfill a crucial function from the preventive standpoint: (1) the possibility of offering mourning mothers psychological support in addition to medication immediately after the loss, and (2) the possibility for the mother of freeing herself from a strong oedipal link with the deceased child.