Background. The study of early trajectories of emotional development may be crucial for detecting cases of depression and peculiarities of disease in children under the age of three, when early intervention may give the so-called «window of opportunity» for greater therapeutic effect. 

Objective. The objective of this paper is to review the literature on the issue of depression in children of infantile and early age and to identify risk factors for the development of depression in children of infantile and early childhood, particularly maternal depression. 

Design. The reference literature on the subject of maternal and child depression is analysed. The study aimed at obtaining data on depressive symptoms in 233 mothers of infants with congenital heart disease during the period of surgical treatment was conducted. 

Results. The paper provides evidence that maternal depression negatively affects child-parent interaction and is a factor of developing depression in the child. Analysis of the results shows that the level of depressive symptoms in mothers of children with CHD in the period of surgical treatment (clinical group) shows that in mothers of children with congenital heart disease 27.1 per cent reveal subclinical depression, and 17.7 per cent reveal severe depression (two days before heart surgery). Two weeks after surgery 30.04 per cent of mothers had the symptoms of subclinical depression and 18.22 per cent showed signs of severe depression, which was a negative factor in the psychological development of children of the age under consideration. 

Conclusion. The phenomenon of depression in children of infantile and early age remains a topic of further discussion for the scientific community. However, it is clear that maternal depression, if it does not cause reciprocal depression in the child, usually makes a negative contribution to the child’s mental development that requires further iresearch.