The purpose of this study was to examine the social support network of mothers with high risk infants and the relation between support and mother-infant interactive behavior. Two issues were investigated: who gave what kind of support to the mother as a function of her infant's birth status; and the relation between type of support and mother-infant interaction in risk and nonrisk dyads. Subjects were 90 infants and their mothers who participated in a longitudinal study on the consequences of high risk birth. Infants were classified by maturity and health into four diagnostic groups: healthy and sick preterm and healthy and sick term. Families participating were all poor, inner city residents of New York City. Sixty-five percent were Hispanic and 28 percent were Black. The remaining seven percent were Caucasian. Results indicate that the number of persons giving support and the type of support given is related to the health status of the child at birth. This differential support may mediate the mother's interactive behavior with her infant during the early months of life. Support to the mother of a sick infant, whether that support involves goods or services, seems to positively reinforce the mother's behavior toward her infant, facilitating more proximal and less distal interaction during the early months of infancy. (RH)