Family Structure and Child Outcomes

Many children growing up in households with nontraditional family structures, such as single-mother or stepfamilies, do at least as well as their peers (Amato Reference Amato2010). On average, however, they are disadvantaged on a wide range of outcomes compared to children growing up in traditional two-parent families. For instance, several studies have documented that they have lower levels of cognitive ability, noncognitive skills, educational attainment, income, and psychological well-being (Amato Reference Amato2000, Reference Amato2010; Härkönen, Boertien, and Bernardi Reference Härkönen, Bernardi and Boertien2017). These associations are in general relatively modest in size (Amato Reference Amato2000) in comparison to other socioeconomic background characteristics such as parental education (Bernardi and Boertien Reference Bernardi and Boertien2016), have been relatively stable across time (Gähler and Palmtag Reference Gähler and Palmtag2015; Li and Wu Reference Li and Wu2008; Sigle-Rushton, Hobcraft, and Kiernan Reference Sigle-Rushton, Hobcraft and Kiernan2005), but vary to some extent across countries (Hampden-Thompson Reference Hampden-Thompson2013; Pong, Dronkers, and Hampden-Thompson Reference Pong, Dronkers and Hampden-Thompson2003).

What is it about family structures and transitions between them that could have an influence on children’s outcomes? Some authors have argued that it is the stability of a family structure rather than the particular characteristics of a family structure that matters for children’s development. The transition from one family structure type to another (e.g., the exit or the entrance of a parent or stepparent) creates a new situation to which children have to adapt, this might interfere with the development of cognitive and noncognitive characteristics (Fomby and Cherlin Reference Fomby and Cherlin2007; Waldfogel, Craigie, and Brooks-Gunn Reference Waldfogel, Craigie and Brooks-Gunn2010). To test this hypothesis empirically, several studies compared children living in stable nontraditional families to stable two-parent families and other family forms. In general, little empirical support has accumulated for the “family stability” perspective. Single-parent families often do worse compared to two-parent families also if they are stable throughout childhood (Magnuson and Berger 2010; Mariani, Özcan, and Goisis Reference Mariani, Özcan and Goisis2017), and the separation of a two-parent family appears to be more impacting for children’s outcomes than other family transitions (Bzostek and Berger Reference Bzostek and Berger2017; Lee and McLanahan Reference Lee and McLanahan2015).

The characteristics particular to certain family structures and transitions therefore appear to be responsible for its associations with child outcomes. The specific family structures and transitions that have received most attention are single-parent families (McLanahan, Tach, and Schneider Reference McLanahan, Tach and Schneider2013), the separation of two-parent families (Härkönen, Bernardi, and Boertien Reference Härkönen, Bernardi and Boertien2017), and the formation of a family including a stepparent (Sweeney Reference Sweeney2010). Characteristics held responsible for the effects of living with a single parent include less authoritarian parenting styles, obstacles to employment for the co-resident single parent, and access to resources of the non-resident parent (Amato Reference Amato2010; McLanahan and Sandefur Reference McLanahan and Sandefur1994; Seltzer Reference Seltzer, ldham and Melli2000). Parental separation, besides implying a transition to a single-parent family, can also come with family conflict and financial costs (Cherlin Reference Cherlin1999; Kalmijn, Loeve, and Manting Reference Kalmijn, Loeve and Manting2007; Pryor and Rodgers Reference Pryor and Rodgers2001; Uunk Reference Uunk2004). Many studies find the income losses related to parental separation to be responsible for a large part of its effects on educational outcomes (Jonsson and Gähler Reference Jonsson and Gähler1997; McLanahan and Sandefur Reference McLanahan and Sandefur1994; Thomson, Hanson, and McLanahan Reference Thomson, Hanson and McLanahan1994). Parental separation can also have a negative impact on psychological well-being, both in the short and the long term (Amato Reference Amato2010; Härkönen, Bernardi, and Boertien Reference Härkönen, Bernardi and Boertien2017), which can translate into poorer educational performance. Stepparents can provide time and financial resources that can compensate for some of the disadvantages experienced by single parents. Children living with a stepparent, however, appear to be more similar in their outcomes to their peers living with a single parent compared to peers living with two biological parents (Gennetian Reference Gennetian2005; Jonsson and Gähler Reference Jonsson and Gähler1997; Thomson, Hanson, and McLanahan Reference Thomson, Hanson and McLanahan1994).

The documented association between family structure and child outcomes could also be due to endogeneity, and hence be spurious. Variation in child outcomes across groups might reflect other processes that are both related to family structures and transitions as well as child outcomes. A major suspect in this respect is socioeconomic disadvantage of parents that might influence both child outcomes and the likelihood to enter a given family structure. In many countries, socioeconomically disadvantaged mothers are more likely to have children outside a union (Perelli-Harris et al. Reference Perelli-Harris, Kreyenfeld and Kubisch2010) and to separate after forming a union (Härkönen and Dronkers Reference Härkönen and Dronkers2006; Matysiak, Styrc, and Vignoli Reference Matysiak, Styrc and Vignoli2014). Associations between family structures and child outcomes might therefore reflect socioeconomic disadvantages that were already present before family formation or before a family transition took place.

In the study of the effects of parental separation, family conflict has been marked as an additional possible source of endogeneity. Many families who break up are likely to experience high levels of conflict before separation. In that case, parental conflict might both lead to a separation and have consequences for children’s outcomes. The actual separation of the parents could in that case have little extra consequences for children’s outcomes (Demo and Fine Reference Demo and Fine2010; Dronkers Reference Dronkers1999; Härkönen, Bernardi, and Boertien Reference Härkönen, Bernardi and Boertien2017).Footnote ¹

Several methods have been employed to monitor or control away the possible influence of these sources of endogeneity (see McLanahan, Tach, and Schneider Reference McLanahan, Tach and Schneider2013, and Härkönen, Bernardi, and Boertien Reference Härkönen, Bernardi and Boertien2017 for overviews). Whereas in some studies associations of family structure with child outcomes disappear, they persist, at least to some extent, in most studies (McLanahan, Tach, and Schneider Reference McLanahan, Tach and Schneider2013). Associations were more often found to be spurious once looking at cognitive ability, whereas they often appeared of a more causal nature once studying educational attainment (Bernardi and Boertien Reference Bernardi and Boertien2016; McLanahan, Tach, and Schneider Reference McLanahan, Tach and Schneider2013). The actual role of family structure in affecting inequality of opportunity is therefore likely to depend on the outcome variable considered. Nonetheless, given that educational attainment is a key socioeconomic outcome, family structure appears to matter for children’s chances in life at least to some extent.

Prevalence of Family Structure Types and Its Social Stratification

Family structure does thus appear to matter at least to some extent for children’s outcomes. However, whether and to what extent variation in family structure also contributes substantially to the observed inequality of opportunity between socioeconomic groups depends crucially on whether nontraditional family forms are common, and whether variation in family structures is socioeconomically stratified.

Giving birth as a single mother has been traditionally more common among women with lower socioeconomic status, but it is still an uncommon course of events in most countries, with the Czech Republic, Russia, the United Kingdom and the United States as some exceptions (Andersson, Thomson, and Duntava 2016; Mariani, Özcan, and Goisis Reference Mariani, Özcan and Goisis2017). Most episodes of living in a nontraditional family therefore start after the break-up of a two-parent family. The extent to which parental separation is socially stratified (i.e., correlated with socioeconomic characteristics) differs across countries, especially once looking at the socioeconomic status of the mother (Härkönen and Dronkers Reference Härkönen and Dronkers2006; Matysiak, Styrc, and Vignoli Reference Matysiak, Styrc and Vignoli2014). Explanations for variation in the socioeconomic gradient of divorce often go back to Goode (Reference Goode, Bendix and Lipset1962), who argued that when divorce is relatively uncommon, individuals need resources to overcome social, economic, and legal barriers to divorce. In such situations, the socioeconomic gradient of divorce will be more positive, but this gradient is expected to reverse to negative once barriers to divorce fade out and also those with fewer resources can divorce. The supposed greater stress experienced by disadvantaged couples will eventually cause them to divorce more once barriers to divorce cease to play a key role (Boertien Reference Boertien2012; Conger, Conger, and Martin Reference Conger, Conger and Martin2010; Härkönen and Dronkers Reference Härkönen and Dronkers2006). In addition to Goode’s long-standing narrative about why the socioeconomic gradient of divorce would become negative, contemporary reasons have been proposed as to why the socioeconomically advantaged are less likely to divorce. These include a higher prevalence of egalitarianism among the educated, which could stabilize relationships (Esping-Andersen et al. Reference Esping-Andersen, Boertien, Bonke and Gracia2013; Goldscheider, Bernhardt, and Lappegård Reference Goldscheider, Bernhardt and Lappegård2015), and greater internal barriers to divorce caused by common investments and commitment to relationships (Boertien and Härkönen Reference Boertien and Härkönen2018).

Table 7.1 shows the prevalence of different family types and the extent to which they are more common among low-educated mothers across countries. If we take mother’s education as a proxy for a family’s socioeconomic position, these numbers provide an indication of the scope for family structure to affect socioeconomic inequality of opportunity across countries. As discussed above, disadvantageous family types should be fairly common and concentrated among socioeconomically disadvantaged families in order to make a substantial contribution to inequality of opportunity.

The table combines information on the percentage of mothers who are single and its stratification by mother’s education. This classification is based on Härkönen’s (Reference Härkönen2017) results using cross-sectional data from the Luxembourg Income Study (LIS) for the period 2011–2015 (or 2006–2010 if recent data are missing).

The more prevalent single motherhood, and the more negative the association between mother’s education and single motherhood, the more likely family structure is to contribute to socioeconomic inequality of opportunity. Hence, in countries toward the bottom right corner of the table, such as Australia, Denmark, East Germany, and the United Kingdom, family structure is more likely to play a role in amplifying socioeconomic inequalities, whereas this is less likely to be the case in countries toward the upper-left corner, such as Hungary, Italy, and Serbia. Estimates of the accumulated exposure toward single parenthood across childhood based on union histories indicate a similar ranking of countries (for the countries with data available), but with France and the Czech Republic being among the countries with the highest percentage of children ever exposed to single parenthood (Andersson, Thomson, and Duntava 2016).

Differences in the Effects of Family Structure across Socioeconomic Groups

A final key factor that determines to what extent family structure contributes to socioeconomic inequality of opportunity is the heterogeneity in its effects on child outcomes across groups. It could be that family structure is socially stratified and that it matters for child outcomes on average, but that its effects are restricted to socioeconomically advantaged children. In that case, its effects on socioeconomic inequality of opportunity will still be limited. In contrast, if family structure especially matters for the disadvantaged, the contribution of family structure to inequality of opportunity might be bigger than expected.

Should we expect heterogeneity in the effects of family structure according to socioeconomic status of families? An in-depth of discussion of this issue can be found in Bernardi and Boertien (Reference Bernardi and Boertien2017b). Two competing expectations can be formed in that regard. On the one hand, children from socioeconomically advantaged backgrounds might have more resources to deal with the challenges posed by living in a nontraditional family form. On the other hand, children from socioeconomically advantaged backgrounds might have more to lose from an absent parent. It could be harder for nonresident parents to transmit their cultural, social, and economic capital to their children (Coleman, Reference Coleman1988). Following Bernardi and Radl (Reference Bernardi and Radl2014), these competing expectations can be labeled as the “compensatory” and “floor effect” hypotheses respectively (see also Chapter 6). Kearney and Levine (Reference Kearney and Levine2017) described it in more economic terms as variation in the “marriage premium for children” according to socioeconomic background.

Studies on differences in the effects of family structure according to socioeconomic background have accumulated rapidly over the last years (Bernardi and Boertien Reference Bernardi and Boertien2017b) and do not all come to the same conclusions. Studies looking at educational attainment mostly find that children from advantaged backgrounds are affected more by parental separation (Bernardi and Radl Reference Bernardi and Radl2014; Kearney and Levine Reference Kearney and Levine2017; Martin Reference Martin2012; McLanahan and Sandefur Reference McLanahan and Sandefur1994). A recent study on the United Kingdom (Bernardi and Boertien Reference Bernardi and Boertien2016) documented how this pattern can to an important extent be explained by changes in family income following separation. Not only do children with higher educated parents lose more family income following separation, these losses in income are also more consequential for their college attainment. Given that family income matters less for the educational attainment of socioeconomically disadvantaged children (as family income could be too low to invest in education to begin with), losses in family income due to separation are less consequential for them (Bernardi and Boertien Reference Bernardi and Boertien2016).

Results from studies on other outcomes such as cognitive ability and psychological well-being come to more mixed conclusions with both possibilities finding support across studies (Augustine Reference Augustine2014; Grätz Reference Grätz2015; Mandemakers and Kalmijn Reference Mandemakers and Kalmijn2014; Ryan, Claessens, and Markowitz Reference Ryan, Claessens and Markowitz2015). Results depend crucially on whether one looks at heterogeneity according to maternal or paternal resources, as maternal resources are often directly accessible to children living with a single parent, whereas access to the resources of the father could be more complicated. The results of most studies can indeed be aligned with a narrative where effects of family disruption are larger when maternal resources are low and paternal resources are high (Bernardi and Boertien Reference Bernardi and Boertien2017b).

The context studied also appears consequential for conclusions. For instance, Grätz (Reference Grätz2015) provided one of the few results on Germany, and found that only the school performance of socioeconomically disadvantaged children is affected by parental separation. Studies on Italy, the Netherlands, and Sweden find smaller effects for children with resourceful mothers (Albertini and Dronkers Reference Albertini and Dronkers2009; Fischer Reference Fischer2007; Jonsson and Gähler Reference Jonsson and Gähler1997), but larger effects for children with resourceful fathers (Fischer Reference Fischer2007; Jonsson and Gähler Reference Jonsson and Gähler1997). Single-country studies on the United Kingdom and the United States in general support the conclusion that socioeconomically advantaged children are affected more by separation (Biblarz and Raftery Reference Biblarz and Raftery1993; Mandemakers and Kalmijn Reference Mandemakers and Kalmijn2014; Martin Reference Martin2012; McLanahan and Sandefur Reference McLanahan and Sandefur1994).

Bernardi and Radl (Reference Bernardi and Radl2014) documented the extent to which effects of parental separation on educational attainment differ by parental education across countries. They found, overall, that socioeconomically advantaged children were affected more by parental separation than socioeconomically disadvantaged children. Importantly, however, these differences in effects were smaller or even the opposite in countries where ability tracking in schools occurs at early ages. If crucial transitions in children’s school careers take place at an early age, separations taking place after that age will have small effects on children’s educational attainment (Bernardi and Radl Reference Bernardi and Radl2014), reducing the estimated influence of parental separation experienced during childhood when averaged across ages.

In general, our reading of the empirical evidence is that socioeconomic heterogeneity in the effects of family structure tends to limit the influence family structure has on inequality of opportunity. In any case, there is no strong evidence that the consequences of growing up in a nontraditional family are greater for children from socioeconomically disadvantaged backgrounds, and hence, that heterogeneity in the effects of family structure would be another factor contributing to the accumulation of disadvantages. Whether this is indeed the case is an empirical question that has so far been addressed only on few occasions.

Quantifying the Contribution of Family Structure to Inequality of Opportunity

We are now in a position to go back to the key question of this chapter: How large is the contribution of variation in family structures to inequality? This question has been central to many studies on income inequality and poverty. Various decomposition and simulation techniques have been used to estimate how much changes in family structure have contributed to changes in income inequality and poverty over time (M. A. Martin Reference Martin2006; McLanahan and Percheski Reference McLanahan and Percheski2008; Western, Bloome, and Percheski Reference Western, Bloome and Percheski2008). Studies on the United States in general come to the conclusion that family structure has been consequential for inequality. A review of the literature stated that between 11% and 41% of the increase in income inequality over the last decades in the United States can be attributed to increases in female-headed households (McLanahan and Percheski Reference McLanahan and Percheski2008). Evidence for other countries is more mixed with one study arguing that family structure only matters for income inequality in the United States (Esping-Andersen Reference Esping-Andersen2007) and other studies finding an income inequality amplifying effect for family structure across sixteen countries (Kollmeyer Reference Kollmeyer2013). A comparative study on poverty among single mothers comes to a similar conclusion (Härkönen Reference Härkönen2017).

That variation in family structures matters for income inequality and poverty, however, does not automatically imply that it also matters for inequality of opportunity between children coming from different socioeconomic groups. Few studies have, until now, aimed to quantify the extent to which family structure could explain differences in child and adult outcomes between individuals coming from socioeconomically advantaged and disadvantaged backgrounds.

Bernardi and Boertien (Reference Bernardi and Boertien2017a) presented such estimates of the contribution of family structure to socioeconomic background differences in educational attainment for four countries: Germany, Italy, the United Kingdom, and the United States. Their main question was to what extent differences in the likelihood of attaining tertiary education between children with higher and lower educated parents could be explained by family structure. Their results are summarized in Figure 7.1, which displays observed differences in college attainment between individuals with a lower (ISCED 1–2) and higher (ISCED 5–6) educated mother. These observed differences are compared to predicted differences between both groups of individuals in the hypothetical situation that all children would have grown up in a two-parent family.

Figure 7.1 Actual and predicted university attainment in hypothetical situation “where all children grow up with both parents in the household”

Figure 7.1 reveals that, in all four countries, differences in college attainment depending on maternal education are predicted to be very similar to observed differences in the hypothetical situation that all individuals would have grown up in a two-parent household. This suggests that the explanatory power of family structure is limited.

The reasons for this result differed according to country. In Italy, the number of children living in a nontraditional family was too small (see Table 7.1) to have a major impact on inequality of opportunity. In Germany, family structure was not (yet) clearly stratified according to parental education, preventing its influence on inequality of opportunity. In the United Kingdom and the United States children of lower educated parents were more likely to grow up in a nontraditional family structure. This was most clearly so in the United States where differences in college attainment between individuals with lower and higher educated parents were estimated to be 10% lower if family structure would not be stratified by parental education. However, in both countries children of higher educated parents were more negatively affected by growing up in a nontraditional family. This heterogeneity in effects almost entirely canceled out the effects of the stratification of family structure by parental education.

A lack of such “diverging destinies” due to variation in family structures in the United States has also been documented in another study using a similar approach (Alamillo Reference Alamillo2016). However, evidence quantifying the possible role of variation in family structures is limited to studies on educational attainment. It could well be that socioeconomic background differences in other outcomes are amplified by variation in family structures.

Discussion and Conclusion

Does the result that family structure can explain little of socioeconomic background differences in educational attainment imply that family structure does not matter for socioeconomic inequality of opportunity in general? More evidence is needed before such a conclusion can be reached. The existing evidence quantifying the contribution of family structure is limited to studies on educational attainment and current research is limited to a small set of countries and time periods.

Even though tertiary education is an important socioeconomic marker, it could be that family structures and transitions between them are important for socioeconomic background inequalities in other outcomes such as income, status, health, or even secondary education. Whether this is the case depends on how strongly family structure is related to these outcomes, and how this relationship varies between socioeconomic groups. Kearney and Levine (Reference Kearney and Levine2017) argued that the additional resources that a second parent (in their framework the father) brings to the household matter less for socioeconomically disadvantaged children when the outcome is only attained by relatively few people, as is the case with tertiary education. This may explain why higher educational attainment is the outcome for which the clearest evidence exists that socioeconomically advantaged individuals are more negatively affected by growing up in a nontraditional family (Bernardi and Radl Reference Bernardi and Radl2014; Martin Reference Martin2012; McLanahan and Sandefur Reference McLanahan and Sandefur1994). For other outcomes, such as psychological well-being and cognitive ability, evidence is less uniform (Grätz Reference Grätz2015; Mandemakers and Kalmijn Reference Mandemakers and Kalmijn2014).

Kearney and Levine made a contrasting argument for outcomes attained by the majority of the population, such as living out of poverty. In such cases, an inverted U-shaped pattern is predicted to be observed with both the most-disadvantaged and advantaged individuals benefiting the least from an additional parent’s resources. This is because socioeconomically advantaged single parents have sufficient resources to enable their children to attain such outcomes, while for many of the most-disadvantaged children, the additional resources of a second parent would still not bring them to a level that enables them to attain “basic outcomes.” If family structure indeed matters little for the attainment of “basic outcomes” by socioeconomically advantaged individuals, its contribution to inequality of opportunity might be greater once considering adult outcomes such as secondary education, employment, and living without debt. Conversely, its role in creating unequal access to outcomes attained by a smaller proportion of the population such as home ownership and other assets might be more limited because, like tertiary education, these are outcomes that advantaged individuals may be less likely to attain if they lose immediate access to the resources of a second parent in the household.

Can we expect family structure to matter more for socioeconomic background inequality of opportunity in contexts that have not been studied so far? Returning to the above discussion on the conditions under which family structure can matter provides clues to answer this question. First, nontraditional family structures have to be common and be socially stratified in order to impact on inequality of opportunity. Both the prevalence and social stratification in single parenthood have continued to increase in many countries during the latter decades (Härkönen Reference Härkönen2017), whereas most of the above results pertain to individuals born in the 1970s and 1980s (as educational attainment was measured around age 30). Stratification in family structures can therefore have become more important for inequality of opportunity over time. The role of family structure also remains unclear in countries where educational differences in family structures are relatively large but which have not featured in previous studies (such as Australia, Denmark, and Republic of Ireland [see Table 7.1]).

Second, the (negative) effects of family structures on the outcomes studies have to be relatively strong. Family structure effects are found in each country and they have remained relatively stable over time, despite the increase in nontraditional families (Härkönen, Bernardi, and Boertien Reference Härkönen, Bernardi and Boertien2017). An important implication of the insight that the role of family structure in the intergenerational reproduction of inequality is contingent on effect size is that intergenerational inequality can be potentially addressed by targeting the effects of family structure on child outcomes (cf. Cohen Reference Cohen, Amato, Booth, McHale and Van Hook2015). Family structure effects on economic outcomes – such as child poverty (Härkönen Reference Härkönen2017) – are readily modified by public policies, but findings suggesting that the effects on school performance can depend on social policies (Pong, Dronkers, and Hampden-Thompson Reference Pong, Dronkers and Hampden-Thompson2003) or the features of the educational system (Bernardi and Radl Reference Bernardi and Radl2014) support that public policies can address the consequences of family change more broadly. Family change need not inevitably lead to increasing inequality, and whether it does can depend on appropriate policy measures.

Third, the impact of variation in family structures on inequality of opportunity will be particularly large if family structure matters most for socioeconomically disadvantaged families. Many studies have shown, instead, that family structure effects are stronger for children from socioeconomically advantaged backgrounds. This particular heterogeneity in the consequences of growing up in a nonintact family reduces the contribution of family structures to the overall inequality of opportunity. It still remains unclear for many countries and outcomes whether heterogeneity in the effects of family structure exists and, if so, whether socioeconomically disadvantaged children are affected more.

All in all, however, the example from the United States is instructive. This is a context where effects of growing up in a nonintact family are large (Hampden-Thomson Reference Hampden-Thompson2013) and strongly socially stratified (Härkönen Reference Härkönen2017), but nonetheless the consequences for equality of opportunity are small because of larger consequences associated with nonintact families experienced by advantaged children. Moreover, inequality of opportunity would be only 10% lower if family structure effects were homogenous across socioeconomic groups (Bernardi and Boertien Reference Bernardi and Boertien2017a). Therefore, it is unlikely that the contribution of family structure to inequality of opportunity in education will be very large in other contexts. The overall conclusion of this chapter thus remains: Currently it does not appear to be the case that family structure contributes to inequality of opportunity between children of different socioeconomic groups in a major way. This conclusion does not mean that family structure does not matter per se for children’s outcomes. Children growing up in nontraditional families do, on average, differ in their outcomes from their peers growing up in stable two-parent families and are overrepresented among children living in poverty (Härkönen Reference Härkönen2017). Family structure is therefore a factor to take into account once studying income inequality, poverty or the characteristics of the most-disadvantaged children. Overall, however, the argument that variation in family structure is a major engine behind socioeconomic inequality of opportunity is not yet empirically supported.