The present study assessed whether birth weight, maternal child rearing behaviors, and maternal intelligence combine in an additive or in a non-linear interactive fashion to influence cognitive performance in a sample of 24-month old full-term appropriate and low birth weight Jamaican children. Child cognitive performance was measured using the Griffiths Scale and a laboratory based assessment of the amount of time the child utilized different levels of play behavior. Mothers were videotaped while playing with their children under different instructional conditions and videotapes were coded for 8 maternal interaction patterns. Maternal verbal intelligence was assessed using the PPVT. Results supported the operation of both additive co-action as well as non-linear interactive processes. Birth weight, maternal behaviors toward her child and maternal intelligence predicted child cognitive performance. In addition, low birth weight infants were either less sensitive to facilitative aspects of maternal behaviors and/or more sensitive to maternal inhibitory behaviors than were appropriate birth weight infants. Further, child rearing behaviors of more intelligent mothers were a stronger influence on their child's cognitive performance than those of less intelligent mothers, even when there were no differences in the level of behaviors of more or less intelligent mothers.