This chapter describes two longitudinal intervention studies of the family during two early family transitions: first-time parenthood and the first child's entrance into school. We show that these major normative life transitions are accompanied by stress, which increases the risk of distress in parents and children, even in relatively well-functioning families who are not yet seeking psychological help. Our research is part of a new wave of studies that examine children's development from a family systems perspective. Although it seems obvious today that parents' styles of interacting with their children play a central role in their children's adjustment and behavior problems, only recently have results from family studies documented what clinicians have written about for years: When the relationship between the parents is troubled, children tend to have problems at home or at school. Observational studies show impressive correlations between prebirth marital quality and subsequent parenting behavior with infants (Cox, Owen, Lewis, & Henderson, 1989; Grossman, Eichler, & Winickoff, 1980; Heinicke, Diskin, Ramsay-Klee, & Oates, 1986). More harmonious marriages have been linked with greater developmental progress in infants and toddlers (Dickie, 1987; Goldberg & Easterbrooks, 1984), preschoolers (Kerig, Cowan, & Cowan, 1993; Miller, Cowan, Cowan, Hetherington, & Clingempeel, 1993), and young school-age children (Brody, Pellegrini, & Sigel, 1986; Cowan, Cowan, Schulz,

& Heming, 1994; Katz & Gottman, 1994). Just as some studies show that good marriages promote children's competence and maturity, others show that prolonged marital conflict and marital dissolution tend to be associated with cognitive delay, school difficulties, and antisocial or withdrawn behavior in the early school years (Cummings & Davies, 1994; Fincham, Grych, & Osborne, 1994; Hetherington, Cox, & Cox, 1982).