This research project investigates concurrent and longitudinal contributions of maternal and paternal activity to toddler language and play competencies in the second year of life. Domains of parental activity include didactic attention focusing, interpersonal affective communication, and control over object-centered exchanges. Several major data sets have been collected on parental style, on toddler competencies, and on the independent and joint contributions of parental style to toddler abilities. Each of these data sets is multifold, and analyses of results have formed the bases for several different, but related, projects to be described herein.