The present study used observed parent-child interactions to examine how maternal and paternal insensitivity across 24 to 36 months were similarly or differentially manifested in shaping school readiness in language and self-regulation skills among children from low-income families. Further, we tested whether children's adaptive engagement mediated the relations between parental insensitivity and school readiness. To these ends, this study used extant data from the Early Head Start Research and Evaluation Study (N = 453 families of mothers, fathers, and children; 51% girls). (author abstract)