A child is part of a larger family system and the family, in turn, is part of a broader neighbourhood or community system. Consequently, changes in the family may affect the child and changes in the child, the family. Thus the basic etiological factors for caries are influenced by a number of indirect factors. The aim of this descriptive study was to investigate some of these indirect factors in families of children who had developed carious lesions at one or two years of age. By using a combination of interviews, questionnaires and video recordings, it was possible to obtain information regarding mental health, psychosocial background, life events, and family interaction. The results show that in all the investigated families, life events had occurred, that had caused a great deal of stress. From a descriptive point of view there does not seem to be a typical family in which infants develop caries. However, certain psychosocial factors could be essential for the development of caries in infants. Since family function, family interaction and life events influence many aspects of children's life, dental personnel must be aware of the repercussions this may have upon oral health in infants and toddlers.