If looks could heal: Child health and paternal investment

Abstract

Data from the first two waves of the Fragile Family and Child Wellbeing study indicate that infants who look like their father at birth are healthier one year later. The reason is such father–child resemblance induces a father to spend more time engaged in positive parenting. An extra day (per month) of time-investment by a typical visiting father enhances child health by just over 10% of a standard deviation. This estimate is not biased by the effect of child health on father-involvement or omitted maternal ability, thereby eliminating endogeneity biases that plague existing studies. The result has implications regarding the role of a father's time in enhancing child health, especially in fragile families.

Introduction

Income inequality in the US increased substantially since the 1990s. Many dispute the underlying causes, but few can disagree that single-parent households tend to fall at the bottom of the distribution. Further, children in these households are at a disadvantage, which likely affects them throughout their lives.

On December 10, 2014, the White House held a summit on Early Education. The key recommendation emphatically endorsed investing in early childhood development (including health). According to one speaker, “[t]he way parents interact with their children, the amount of time they spend with them and the resources they have …greatly affect their children's potential for leading flourishing lives” (Heckman, 2014). Time inputs of both parents appear to be even more important than money investments in producing quality children (Del Boca et al., 2014). In this regard, the prevalence of children currently living in low-income single mother homes is of concern. In 2016, 17.2 million (nearly 25%) children under age 18 were living only with a mother and 40% of those lived below the poverty line (U.S. Census Bureau, 2016). These children are more likely to be food insecure (Nord et al., 2005), and have less access to parental investment especially from absentee fathers (Jones and Mosher, 2013). But, as will be explained, the impact of nonresident father-involvement on child health has not been adequately studied. In this paper, we consider whether early investments by nonresident fathers improve child health. Determining this is important given that child health is strongly linked to future education, adult health and eventual labor market success (Case et al., 2005, Currie, 2009, Campbell et al., 2014).

The ‘parent–child family’ model of Jacobson (2000) explains that parents allocate material and time inputs to the production of child health, in addition to their own health, in order to maximize the family's utility. Bolin et al. (2002) extend the model to consider, inter alia, the effects of family policies on child health when parents are divorced. Their model implies that greater nonresident father contact (via joint custody) or child support would raise the amount of child health. Frequent contact likely provides more parental time to supervise children, manage harmful exposures, gather information and attend to their health needs, and share parenting tasks. Nonresident fathers might also be attentive and careful in child interaction to prevent health problems and thereby secure future visiting opportunities (Nepomnyaschy and Donnelly, 2015). Child support may increase the mother's ability to purchase more or better health inputs, and also increase father visitation (Del Boca and Ribero, 2001). An alternative perspective is a visiting father might stir up conflict or put strain on a mother's economic resources. This in turn affects parenting practices and maternal depression (Slade, 2013), which makes children more susceptible to health problems or emotional distress.

A growing empirical literature finds that children in single-mother families have lower health than children in two-parent families (e.g. Angel and Worobey, 1988, Bramlett and Blumberg, 2007, Harknett, 2009). However, studies regarding the impact of nonresident fathers’ involvement are scarce and provide mixed conclusions. Menning and Stewart (2008) find nonresident father contact is related to a greater risk of adolescent obesity. Yet, somewhat contradictory, other studies find that frequent visitation is related to fewer food acquisition problems in households with 0–17 year old children (Garasky and Stewart, 2007) and healthier adolescent eating habits (Stewart and Menning, 2009). For kindergarten children, Hofferth and Pinzon (2011) find no effect of nonresidential fathers’ child support payments and contact on child health after parental separation. At the same time, Baughman (2014) shows child support lowers the odds of poor health for children 2–15 years old. When children are 1–5 years old, Nepomnyaschy and Donnelly (2015) find nonresident father engagement insignificantly affects injury risk (similar to Hofferth and Pinzon, 2011); however, their cooperative parenting behavior lowers such risk.

Simply controlling for demographic and socioeconomic factors limits these studies’ facility to control for several possible sources of endogeneity bias. First, poor child health may either deter or induce nonresident father involvement, rather than the reverse in which father involvement augments child health. For example, Reichman et al. (2004) find child health may lead to marital dissolution, and hence lower father involvement. Also, Hofferth and Pinzon (2011) find child health problems lower financial support. Ignoring such reverse causation creates an ambiguous estimation bias. Second, a protective, self-reliant and competent mother may discourage (‘gatekeep’) father engagement in child-rearing activities (Allen and Hawkins, 1999, Gaertner et al., 2007); or a mother's time in child care may be a substitute for a father's time (Pailhe and Solaz, 2008). Such maternal factors if ignored can cause a downward bias. Third, a mother who views herself as the sole contributor to her child's health may more likely understate a father's participation, while a mother who merely wishes the father participated more might overstate it. So, mother-reported paternal investment may be measured with error, which can create a downward bias. The overall bias is ambiguous, making it difficult for existing studies to ascertain the causal impact of nonresident fathers on child health.

We introduce a unique approach, with roots in evolutionary sociobiology, to infer the causal impact of nonresident father-involvement on child health. To do so, we make use of an a priori unexpected observation in the Fragile Families and Child Wellbeing data. We find infants born out of wedlock who look like their father at birth (as assessed by both parents in separate and private interviews)¹ have better overall health one-year later, but not at birth. Further, we determine the underlying mechanism for better child health one year after birth in response to father–child resemblance is father involvement, in particular the amount of time a father invests in his purported child. We find the average nonresident father spends about 2.5 days (per month) longer in parenting activities when the child resembles him. Consistent with several studies from evolutionary sociobiology (e.g. Platek et al., 2002, Platek et al., 2003, Platek et al., 2004, Volk and Quinsey, 2002, Volk and Quinsey, 2007), father–child resemblance encourages paternal time-investment, perhaps because doubtful males respond to paternity uncertainty. There is little or no evidence to support other potential mechanisms such as a father's economic provision, his involvement in shared parenting, or maternal parenting. These results support using father–child resemblance as an instrument for the time a father invests in the child to establish a causal link between father's time investment and child health. The validity of the father–child resemblance variable is supported by conducting placebo checks under conditions where such a variable is irrelevant to paternal investment. We find fathers’ time-investment significantly improves child health in single-mother families. Based on a linear combination of five child health indicators, each extra day of time-investment increases child health by over 0.1 standard deviations. It also decreases the probability a child will have reportedly ‘poor’ health by 2 percentage points. Thus, promoting nonresident father time-investment could be a key strategy to reduce child health disparities and thereby secure a greater chance of future educational and career success for children in single-mother families.

The next section presents the literature relating child resemblance to paternal investment. In Section 3, we describe the data and define key variables. In Section 4, we estimate the impact of father–child resemblance on child health and father investment, deduce the mechanism through which such resemblance operates, and provide checks for robustness. Finally, Section 5 provides a conclusion.