Children who present early and severe malnutrition show a deficit in their psychomotor development and specific behaviour disturbances which are recovered to a large extent when receiving integral rehabilitation. During their growth and development process, these children have differences in their intellectual development that cannot be explained as a consequence of the nutritional deficit alone. Therefore, the purpose of this study was to describe and compare from a systemic perspective, some characteristics of the family structure of these children with a history of early and severe malnutrition and who showed a differing intellectual performance at school age. Seven families with infants who had been admitted and treated in a Closed Nutritional Recovery Center of the Corporation for Infantile Nutrition (CONIN) were studied. All the children showed a moderate delay in their psychomotor development on admission, but all had significantly recovered at their discharge. At school age, in four families, the index subject presented an intellectual capacity of greater-than-or-equal-to 70 < 80 and in the other three, children showed an intelligence quotient greater-than-or-equal-to 85. Each family was studied through a semi-structured interview held at the family's home with participation of all its members. Each interview lasted approximately one hour and was filmed with an audio-video equipment. The interviews were later coded using a checklist of behaviour indicators for family interaction. The results revealed differences between the two family groups, both with respect to their parental sub-systems and also in the relations established between the parents and those children with a history of early and severe malnutrition, especially with respect to the paternal sub-system and their index children. The observed differences between the two groups centered mainly on the amount of help that parents give to their children with a history of malnutrition, and the orders given to them. The results obtained are discussed in relation to sexual roles in low-income families and their relation to socioeconomic conditions.