The described study focused on the phenomenon of an "imagined partner" (IP) and its functions in children. The investigators were especially interested in the link between IP and social deprivation outside the family. The experiment involved children aged 7-11 both intellectually intact and suffering from cerebral palsy. All the children consistently displayed fantasies involving IP. The following methods were used: questionnaires for children and parents about the imagined partner; a technique for finding out existing social contacts; parents' observation diaries registering the appearance of IP and the accompanying factors (such as health condition, mood, social contacts etc.). The findings show that consistent fantasizing with the participation of IP is a form of psychological defense whose functions vary depending in different periods of a child's life depending on the child's age, individual living conditions and development of self-awareness.