Coparenting and parenting pathways from the couple relationship to children's behavior problems.

Indirect Effects of Couple Relationship Quality via Parenting and Coparenting

The main theory indirectly linking the quality of the dyadic couple relationship with child socioemotional adjustment, the spillover hypothesis, suggests two main mechanisms involving disruptions to family processes concerning the child ( Erel & Burman, 1995 ). First, tensions in the couple relationship may lead to compromised parent–child interactions (parenting), as parents become less emotionally sensitive to the child’s needs. This idea receives considerable empirical support, in relation to both couple conflict and lower marital satisfaction ( Erel & Burman, 1995 ; Krishnakumar & Buehler, 2000 ). Second, couple relationship problems may undermine supportive coparenting. Coparenting concerns parents’ joint family management and division of labor, agreement on child rearing and support for one another’s parenting ( Feinberg, 2003 ). Although often operationalised as a particular domain of dyadic couple functioning, a family systems approach classifies coparenting as triadic functioning, where the child is also involved ( Talbot & McHale, 2004 ). Empirical work supports a distinction between triadic coparenting and dyadic couple relationship functioning, finding that some couples with a poor dyadic relationship may engage in supportive triadic coparenting, and vice versa ( Feinberg, 2003 ). Nonetheless, positive qualities of the dyadic couple relationship are likely to facilitate supportive coparenting, which may in turn help sustain dyadic parent–child relationships ( Fincham & Hall, 2005 ). Empirical support for the idea that coparenting is an intermediary on spillover paths from the dyadic couple relationship to mothers’ and fathers’ individual parenting comes from several studies of families with young children, (e.g., Holland & McElwain, 2013 ; Pedro, Ribeiro, & Shelton, 2012 ).

The conceptual model in Figure 1 extends the spillover model of couple relationship qualities onto coparenting and parenting ( Erel & Burman, 1995 ; Fincham & Hall, 2005 ), to show their impact on children’s externalizing behavior. It suggests indirect paths from the couple relationship via parenting alone, via coparenting and then parenting, and via coparenting alone. The part of the model extending parenting spillover to impact externalizing problems is well-established, as many studies have linked less positive parenting (e.g., warmth) and more negative parenting (e.g., harsh control) with the development of externalizing problem behavior ( Pinquart, 2017 ). The model also suggests a pathway involving coparenting alone, since there is empirical evidence for independent effects of coparenting and parenting on children’s externalizing behavior ( Teubert & Pinquart, 2010 ). This pathway is less well understood than those involving parenting. Overt coparenting disagreements might model irritability, anger and aggression, disinhibiting the use of such behavior regardless of parents’ individual parenting effectiveness ( Chen & Johnston, 2012 ). Even when the child is not directly exposed to coparenting tensions, lack of cooperation and/or undermining coparenting might model negative behavior strategies, such as noncompliance with rules or bullying ( Murphy, Jacobvitz, & Hazen, 2016 ).

There is mounting empirical evidence for long-term indirect effects of the couple relationship in early childhood on child behavior, via enduring effects on parenting quality. Several longitudinal studies of families with young children have found indirect paths from the couple relationship via positive and negative parenting, acting over one or more years ( Gerard, Krishnakumar, & Buehler, 2006 ; Lindsey, Caldera, & Tankersley, 2009 ; Rhoades et al., 2011 ; Schoppe-Sullivan, Schermerhorn, & Cummings, 2007 ; Stover et al., 2016 ). In contrast, research that explores coparenting as an additional mediator is relatively sparse: two studies ( O’Leary & Vidair, 2005 ; Stroud, Meyers, Wilson, & Durbin, 2015 ) consider both coparenting and parenting as mediators, finding indirect pathways via both types of process to externalizing problems. However, only one study allowed for all the paths suggested by our conceptual model ( O’Leary & Vidair, 2005 ), and neither used a longitudinal design.

In addition to a paucity of research on a more comprehensive set of indirect pathways, there are other notable research gaps left by existing pathway studies of families with young children. The studies cited above examining pathways from the couple relationship to children’s externalizing problems via parenting all used couple conflict or hostility as the main exposure, and there is a need to explore pathways to children’s problems from alternative, more positive dimensions of the couple relationship. There are also question marks over the generalizability of existing studies. All but one ( Gerard et al., 2006 ) of the parenting pathway studies relied on small, convenience samples with little or no allowance for potential confounders. A further limitation of existing longitudinal pathway studies is that they do not generally span the critical period of the child’s transition to school, relating either to preschool ( Lindsey et al., 2009 ; Rhoades et al., 2011 ) or to school-age years ( Gerard et al., 2006 ; Schoppe-Sullivan et al., 2007 ). The one exception covering school transition found that effects of the couple relationship were confined to the preschool period ( Stover et al., 2016 ). More studies are therefore required to establish whether indirect pathways extend from couple relationship quality in early childhood, to impact on school-age externalizing problems.

Study Aims and Hypotheses

This is the first longitudinal study to assess the independent contribution of coparenting, as well as parenting, toward explaining the effects of couple relationship quality during children’s early years on middle childhood externalizing problems. We define relationship quality in terms of overall mutual emotional supportiveness, as this is likely to convey important positive as well as negative dimensions of couple functioning ( Goldberg & Carlson, 2014 ). We assess the couple relationship in infancy as this is a good guide to subsequent supportiveness across the preschool years ( Howard & Brooks-Gunn, 2009 ), and predates the development of behavior problems thereby excluding reverse causation (but not confounding). We assess potential coparenting and parenting mediators mainly in the preschool years (including some information from the school transition period in one of the study samples). Coparenting and parenting of preschoolers is important for the development of executive functioning and secure attachment ( Fay-Stammbach, Hawes, & Meredith, 2014 ; Karreman, van Tuijl, van Aken, & Dekovic, 2008 ; Moss, Cyr, Bureau, Tarabulsy, & Dubois-Comtois, 2005 ; Pérez, Moessner, & Santelices, 2017 ), which in turn protect against externalizing problem development ( Fearon et al., 2010 ; Schoemaker et al., 2013 ). Thus, we are able to study our potential mediators at an important point. Nonetheless, because coparenting and parenting behaviors are moderately stable in early childhood ( Dallaire & Weinraub, 2005 ; Laxman et al., 2013 ), we are likely to also capture the quality of these processes during the child’s infancy and toddler years.

We explore the following hypotheses: (1) couple supportiveness will be associated with reduced childhood externalizing problems in middle childhood and (2) associations will be mediated by supportive coparenting and higher quality mother’s and father’s individual parenting of the preschool child. On the basis of previous literature, finding independent effects of parenting and coparenting on externalizing problems ( Teubert & Pinquart, 2010 ), we expect additive indirect effects of coparenting and parenting constructs, although it is not clear whether coparenting (followed by parenting or alone) channels most of the spillover effect of the couple relationship ( O’Leary & Vidair, 2005 ; Stroud et al., 2015 ). Previous pathway studies also lead us to expect indirect effects involving both negative and positive parenting ( Gerard et al., 2006 ; Lindsey et al., 2009 ; Schoppe-Sullivan et al., 2007 ; Stover et al., 2016 ), but it is not clear where the balance of effects lies. Another unresolved issue is whether spillover has a more pronounced effect on one parent; either the mother as the child’s main caregiver, or the father, whose involvement with the child, as suggested by the fathering vulnerability hypothesis, may be relatively dependent on partner support ( Cummings, Merrilees, & Ward George, 2010 ). Empirical studies addressing the question of whether spillover affects one parent more than the other have inconsistent findings ( Lindsey et al., 2009 ; Rhoades et al., 2011 ; Stover et al., 2016 ; Stroud et al., 2015 ). In connection with our second hypothesis, we explore the following comparisons related to the magnitude of distinct indirect pathways to clarify which mechanisms are more dominant: 1 coparenting (with/without parenting) versus parenting alone,

negative parenting versus positive parenting, and

mother’s parenting versus father’s parenting.

We use two large longitudinal population-based samples, drawn from different countries, with different ethnic and sociodemographic compositions, so similar results will increase our confidence in the generalizability of the mechanisms. The two study samples have distinct, complementary characteristics. The first consists of a sample of stable couple families containing both biological parents coresiding throughout the child’s early years. As a nationally representative sample, the U.K. Millennium Cohort Study (MCS) offers more generalizability than existing studies using convenience samples. The second draws from a large population-based study from the United States, the Fragile Families and Child Wellbeing Study (FFS). This study was designed to oversample unmarried parents, who are underrepresented in research on couple relationship problems in relation to child adjustment. Unlike the U.K. study, the U.S. study included data on couple supportiveness, coparenting, and parenting from non-coresiding couples.

Sample 2: FFS

The FFS is a longitudinal study of families with a child born between 1998 and 2000 in 20 large U.S. cities (>200,000 inhabitants; N = 4,897). It was designed to oversample unmarried couples: these represented three quarters of the sample at baseline, with 40% not living together when their child was born ( Reichman, Teitler, Garfinkel, & McLanahan, 2001 ). Mothers and fathers were interviewed in the hospital within 48 hr of the child’s birth, and follow-up information was collected by telephone when the child was approximately 1, 3, 5, and 9 years old. In-home assessments were performed at 3, 5, and 9 years, and teachers completed postal questionnaires at 5 and 9 years. At child aged 1 year, there were 4,364 families where the mother was interviewed. We excluded families with multiple births ( n = 83), families where the mother was not married or in a romantic relationship with the child’s father ( n = 1,408), and those where neither parent provided information on couple relationship quality ( n = 3), leaving 2,873 eligible families. The analytic sample was limited to 2,069 families where information was available on the 9-year-old child’s externalizing problems from at least one source (parent, teacher, child).

Measures

Here, we outline the main measures used in each data set, indicating where these drew on items from previously validated scales. Internal reliability of measures was generally satisfactory (α > .70). Where reliability fell slightly below this level in either study, reliability of the equivalent measure in the other study was satisfactory. Full details, including sample items, reliability, mean values, and correlations between measures are provided in the online supplemental material . To facilitate comparison of effect sizes, all main measures were standardized prior to analysis.

These were measured at age 11 (MCS) or age 9 (FFS) using information from parents, teachers and children. Supplementary analyses in both study samples used additional parent-reported measures gathered at age 3 (as control variables) and in MCS used parent and teacher reports gathered at age 7 (as supplementary outcome measures).

Parent and teacher reports used the combined conduct and hyperactivity/attentional problems five-item subscales from the Strengths and Difficulties Questionnaire ( Goodman, 1997 ). Child reports used items selected for the purposes of this study on delinquent behaviors, school engagement, bullying, and anger.

FFS

Parent reports (generally from mothers) used items from the combined aggressive and rule-breaking subscales of the Child Behavior Checklist ( Achenbach & Rescorla, 2001 ). Teacher reports used the externalizing problems subscale of the Social Skills Rating System ( Gresham & Elliott, 1990 ). Child reports used the externalizing subscale of the Self-Description Questionnaire ( Marsh, 1990 ).

Primary exposure: Couple supportiveness

Both parents reported on the other’s emotional supportiveness when children were infants (MCS: 9 months; FFS: 12 months). For MCS, parents reported on seven items, including six from the Golombok Rust Inventory of Marital State ( Rust, Bennun, Crowe, & Golombok, 1990 ), concerning the partner’s sensitivity and ability to listen, and the respondent’s feelings of closeness, affection, commitment and happiness in the relationship. For FFS, parents reported on five items concerning the extent to which the partner compromised, listened, empathized, offered encouragement, or expressed affection.

To reflect the dyadic nature of the couple relationship construct, an average of the two parents’ scores was used in the main analysis. Supplementary analyses address the potential relevance of different perceptions of the couple relationship by each parent, which was particularly important given relatively low correlations between ratings of the couple relationship in FFS ( r = .19, p < .001, compared with r = .44, p < .001 in MCS).

Negative parenting

For MCS, this used the eight-item Parent–Child Conflict subscale from the Pianta Child–Parent Relationship Scale ( Pianta, 1992 ). For FFS, this used a measure of harsh discipline, concerning frequency of spanking. (A measure of harsh discipline at ages 3 and 5 (mothers only) was used in supplementary analyses of MCS, for closer comparison with FFS.)

Positive parenting

For MCS, this used the seven-item Parent–Child Closeness subscale from the Pianta Child–Parent relationship scale ( Pianta, 1992 ). For FFS, this used the frequency of parental involvement in seven activities with the child, such as reading stories or playing with toys. (Supplementary MCS analyses used a similar age 5 measure of involvement.)