Was Cinderella just a fairy tale? Survival differences between stepchildren and their half-siblings

Abstract

The death of a parent, particularly the mother, is linked to a suite of negative outcomes across the life-course. Compounding concerns for child outcomes are expectations of poor treatment by step-parents after parental remarriage. Indeed, folk tales of step-parental abuse abound cross-culturally and are embedded into stories taught to children. To understand why child outcomes might be sensitive to levels of relatedness within the household, evolutionary-oriented research targets patterning in parental expenditure in ways predicted to maximize inclusive fitness. In particular, parents are expected to prioritize investments in their biological children. However, stepfamilies are only formed after children experience multiple unfortunate events (e.g. parental loss, poverty), blurring causal interpretations between step-parental presence and stepchild outcomes. Moreover, stepchildren have been shown to be integral to household functioning, caring for their half-siblings and stabilizing relationships. These results challenge narrow views of adaptive behaviour; specifically, that step-parents, unlike biological parents, do no stand to reap fitness benefits from the care that they provide to their stepchildren. To evaluate these critiques, we analyse the survival outcomes of stepchildren. We include over 400 000 individuals from across a natural fertility period (1847–1940) in the United States state of Utah and examine the consequences of parental loss and step-parental introduction. Our analyses yield three key results: (i) exposure to maternal loss in childhood is associated with elevated mortality risk, (ii) parental remarriage does not increase the risk of mortality among stepchildren compared to non-stepchildren who too had lost a parent, and (iii) stepchildren enjoy higher survival than their half-siblings within the same family. Ultimately, this work contributes to the increasingly recognized importance of cooperative relationships among non-kin for childcare and household functioning. This article is part of the theme issue ‘Multidisciplinary perspectives on social support and maternal–child health’.

The differential role of practical and emotional support in infant feeding experience in the UK

“…By taking a capital-based approach to social support, we hope to encourage the idea that 'support is support', irrespective of who it comes from. A nuclear family bias in public health research (see Sear this issue [55]) often causes both the full scope of maternal social support networks to be elided and some supporters to be considered more important than others, which risks stigmatizing 'non-traditional' family forms (see Budds [56] and Schacht [57] this issue). While our data lacks variance for well-established supporters, we see clearer effects for those whose support varies more within the sample, such as brothers and father's-in-law.…”

Who cares for women with children? Crossing the bridge between disciplines

“…In this issue, for example, Gettler et al investigate the mechanism of how paternal provisioning influences child psychobiology in the BaYaka [44], revealing the pathways of how social support can impact child fitness. The fitness consequence, or the current utility, of social support is explored by Schacht et al using a historical dataset from Utah, evidencing how the flexibility of family formations after parental death buffers children from mortality risks [18]. As we demonstrate through this theme issue, exploring social support from different levels encourages diversity in perspectives, leading to a comprehensive understanding of 'who cares' for mothers and children and its consequences.…”

“…Many authors in this issue, us included, highlight the importance of non-maternal caregivers and extended social support across cultures. This includes fathers [13,23,44,49,57], grandmothers and other relatives [13,16,17,23,43,49], as well as non-kin in both informal and formal settings [16,18,23,31,58]. Second, we primarily focus on the individual-level and specific acts of support rather than wider supportive environments.…”

“…With this focus, we present commentaries and research papers on: understanding the need for mother-infant support [15,58]; supporting pregnancy and childbirth [31,40,57]; supporting maternal mental health [14,41,42]; supporting maternal physical health [16,17,43]; supporting infant feeding [13,49] and supporting child survival and development [18,23,44]. These topics bring together diverse literature on multiple elements of social support and maternal-child health, moving past a primary focus on child outcomes.…”

“…Much of what is felt or believed to be 'normal' among researchers, practitioners and policy makers in the West may in fact be comparatively unusual. As Sear and others highlight in this issue [15][16][17][18], the human childrearing system evolved to be cooperative, where mothers and children require extensive support from others [19][20][21][22]. It is only in relatively recent history that nuclear family norms became so widespread [15] and, cross-culturally, childrearing is still widely shared where mothers and children are supported by a diverse range of individuals [16,17,[19][20][21]23].…”