Keywords

Shared physical custody, where children live alternately in their mother’s and father’s homesFootnote 1, produces a new family form (Melli and Brown 2008). In contrast to nuclear families, parents live apart; in contrast to families with sole physical custody, each parent is both resident and non-resident at different times. In this chapter, we identify structural features of families with shared physical custody that differ from those of nuclear families or those of families where one parent has sole physical custody, and discuss the implications for family and kin relationships. Our analysis generates an agenda for future research on the nature and consequences of shared physical custody.

The context for the emerging family form produced by shared physical custody is the conjugal kinship system in which parents and minor children typically live in a their own household separate from extended kin; the parents’ relationship is characterized by emotional as well as economic bonds; and obligations to conjugal family members are expected to be stronger than those to more distant kin (Parsons 1943). In this system, the boundaries of the conjugal family and the nuclear household are identical, and family relationships are constructed and maintained within a fixed space. Coresidence also means that interactions with extended kin usually occur at the same time for all family members and kin support is provided to family members as a group through their common household and economy.

In a conjugal family system, separated parents retain responsibilities to their children and children retain rights to both parents’ resources and care.Footnote 2 The parent-child relationships remain primary, in comparison to relationships with extended kin. The establishment of two households, however, changes the dynamics of the relationship between the two parents, the relationships between each parent and the children, and contact and exchange with extended kin. Children rarely interact with both parents or with both sets of extended kin at the same time and place. They experience their relationship with each parent and with each parent’s extended kin in a different time and place. Until the recent past, the new maternal household was privileged over the new paternal household as the locus for family and kin relationships, i.e., children lived primarily with their mothers and periodically visited their fathers and his kin. When separated parents share physical custody, neither parent’s household is primary.

We begin our analysis below with this transformation in the gendered character of household and family life. We then analyze the structural features of family living that are uniquely produced by shared physical custody (in contrast to nuclear families and sole physical custody), and how they might influence relationships among family members. We further examine the implications of such arrangements for parents’ re-partnering, step-family relationships, and kinship. We cite what scarce evidence exists for our theoretical speculations, noting here that such evidence is currently available only for a limited number of societal contexts.

1 Transformations in the Gendered Division of Labor

The most noticeable feature of families with shared physical custody is the parents’ division of labor. Several scholars have argued that the second stage of the gender revolution requires fathers to take on the same types of responsibility as mothers, i.e., be responsible for 24/7 care and parenting (Bianchi et al. 2012; DeRose et al. 2019). Shared physical custody demands that level of commitment from fathers.

It is not surprising, then, that shared physical custody is most common in Sweden (Bjarnason and Arnarsson 2011), where maternal employment (Oláh and Bernhardt 2008) and men’s family work (Ferrarini and Duvander 2010) have also been in the forefront. Gender-egalitarian norms are strongest in Sweden and more than in other countries emphasize parents’ equal responsibility for earning and caring (Edlund and Öun 2016). Sweden was the first country to allow fathers and mothers to equally share parental leave (Duvander and Lammi-Taskula 2011) and fathers’ responsibilities for child care in Sweden are viewed as critical for making shared physical custody work (Harris-Short 2011).

Gender arrangements are also associated at the micro-level with shared physical custody. The transition from parents and children living together to children living alternatively with each parent is facilitated when couples have achieved relatively high levels of gender equality in paid work and childrearing before separation. Shared physical custody is more likely when the mother has been working full-time before separation (Bonnet et al. 2017; Cancian et al. 2014; Juby et al. 2005; Pelletier 2016; Poortman and van Gaalen 2017; Smyth et al. 2004), even though it also depends to a considerable extent on fathers’ economic contributions (Cashmore et al. 2010; Le Bourdais et al. 2002; Maccoby and Mnookin 1992). Fathers with shared physical custody are more likely to have been engaged in child care and family work and to have expressed more enjoyment of parenting prior to separation compared to fathers without physical custody (Juby et al. 2005; Kitteröd and Wiik 2017; Masardo 2009; Pelletier 2016). Couples with shared physical custody place high value on each parent’s identity as both earner and carer (Bakker and Karsten 2013).

Regardless of a couple’s ideologies, preferences and arrangements prior to separation, shared physical custody in and of itself imposes a high degree of gender equality. In France, for example, mother’s labor force participation is greater when separated parents share physical custody of their children, becoming more similar to that of fathers (Bonnet et al. 2017). Shared physical custody also has implications for the types of work that mothers and fathers do. Mothers are typically expected to require flexibility in their employment conditions in order to care for children; fathers are not. Thus, fathers with shared physical custody may need to change jobs or occupations or may be viewed as problem employees when they take full responsibility for their children (Eriksson 2018). Parents with shared physical custody are more likely than parents without physical custody but less likely than parents with sole physical custody to report that their work interferes with family responsibility (Van den Eynde and Mortelmans 2017). Separated mothers remain more likely to report such conflicts than separated fathers, however, regardless of the residential arrangement.

Because few coresident couples achieve full equality in parenting, shared physical custody provides greater opportunities and demands for father-child interaction than before separation and certainly more than for nonresident fathers. Several studies have demonstrated that children who live alternately with each parent have closer relationships with their fathers than those living primarily with their mothers (Bastaits and Mortelmans 2016; Bastaits et al. 2012; Cashmore et al. 2010; Melli and Brown 2008; Sodermans et al. 2015; Spruijt and Duindam 2010; Vanassche et al. 2013). All of this evidence is cross-sectional and much of the association could result from the selection (as noted above) of the most engaged fathers into sharing physical custody. The potential effect of shared physical custody on father-child relationships therefore remains to some extent theoretical.

Shared physical custody should also generate greater quality between mothers and fathers in leisure, given that each parent has extended periods of time without childcare responsibilities. Limited evidence shows that mothers who share physical custody of their children report more social activities than mothers with sole physical custody; although no such differences are reported for fathers, the result is greater equality for parents who share physical custody in comparison to those who don’t (Botterman et al. 2015; Sodermans et al. 2015).

Overall, then, the family and household lives of parents who share physical custody are much more similar than are those of separated parents who do not, and are likely more similar than parents in nuclear households. In the latter case, there are possibilities to divide earning and caring in unequal ways that are not available to parents whose children live alternately with each of them. As discussed in later sections, the gender transformation in households where children live part but not all of the time also has implications for the gendered character of stepfamilies and relationships with extended kin.

2 Household Structure and Family Relationships

The distinction between weekday and weekend/vacation living is critical to the new family form produced by shared physical custody.Footnote 3 A weekend parent has periods of 24-hour responsibility, but may not have to juggle the simultaneous demands of child care and work. It is possible for children to keep their clothing and other necessities in one place, packing a travel bag for visits to the other parent. When both parents have children during the weekday, each must juggle childcare with other activities at least some of the time and children must have everything they need in both homes. These structural features of daily life appear to be reflected in family members’ perceptions of where the children live; members of families in which children live alternately with each parent view the children as living with both parents; members of families with visiting arrangements are more likely to identify the children’s home as that of the parent with sole physical custody (Bakker and Mulder 2013; Sodermans et al. 2014).

A second structural element of shared physical custody is the “cycle of care” (Steinbach 2018:3), how often children move back and forth. The most common cycle in studies to date is weekly (Bakker and Karsten 2013; Berman 2015; Sodermans et al. 2014). One study found that transitions between homes were most likely to occur in conjunction with the weekend (Sodermans et al. 2014). Thus, children have a stable home-to-school commute during any given week and transfers between homes occurs at breaks in the school and work week. In comparison with families where weekends are typically visiting time with one of the parents, both parents have leisure and work days with children in the home.

The nature of parents’ and children’s time together is fundamentally different in families where children commute between homes than where they live with both parents in the same home or primarily with one parent. In comparison to a two-parent coresidential family, one parent is always there during the time in residence, engaged in everything from mealtime to bedtime, from comfort to discipline, in the same way as for parents with sole physical custody. Each parent-child relationship is constructed more directly, rather than one parent mediating the child’s relationship with the other, giving children greater autonomy and bargaining power (Berman 2015). Full-time engagement may increase feelings of closeness with parents, especially fathers who would otherwise have only visits with their children (Fransson et al. 2018). Children may even spend more time with each parent than do children whose parents live together (Berman 2015). On the other hand, children living alternately with each parent may be exposed to more conflict associated with more frequent contact of the two separated parents (Drapeau et al. 2017).

The sibling experience is also likely to be altered by shared physical custody. When separated parents have more than one child, the siblings generally commute together; residential arrangements where siblings live full-time with different parents are rare (Berman 2015; Meyer et al. 2017). Thus, time with a sibling will not differ across household arrangements. With shared physical custody, however, the siblings share more of daily life with each other than they do with either parent (Winther et al. 2015). Thus, the sibling relationship may gain in importance relative to the parent-child relationships (Berman 2015).

The daily lives of parents with shared physical custody are dramatically different from those of nuclear family parents, parents with sole physical custody, or parents without physical custody. Parents with shared physical custody report their lives as divided into two parts, one in which they are intensely engaged with caring for children and less engaged in work, and the other in which they work long hours with freedom from the scheduling constraints of child care (Bakker and Karsten 2013; Berman 2015). This division also produces a stronger demarcation between family and work, perhaps contributing to overall balance in everyday life. Parents with shared physical custody experience less time pressure than parents with sole physical custody, though more than parents without physical custody (Van der Heijden et al. 2016).

It goes almost without saying that separated parents’ relationship with each other must be of a different character than when both rather than one or the other has primary responsibility for children. The structure of shared physical custody increases the number of conditions to negotiate and the frequency of contact between separated parents. Elements of cooperation as well as conflict will likely be greater than for parents where one has physical custody and the other does not, though cooperation would likely be less than for a nuclear family couple. Parents who do not have a sufficiently cooperative relationship to communicate and coordinate the regular exchange and different living conditions for children are less likely to share physical custody (Pelletier 2016). Most studies find that parents with shared physical custody have less conflict than those where only one parent has physical custody (Maccoby and Mnookin 1992; Pelletier 2016; Spruijt and Duindam 2010; Sodermans et al. 2013; Turunen 2017). The evidence here is, however, cross-sectional, measured after the union dissolution, and could therefore be due entirely to the positive effect of cooperation on sharing physical custody. When shared physical custody is encouraged by a court or by legislation, more high conflict couples are likely to end up with the arrangement (Sodermans et al. 2013). Whether shared physical custody might improve or worsen the separated couple’s relationship is an open question.

3 Household and Family Stability

A key dimension of family life after parental separation is the stability of children’s households. Geographic constraints mean that shared physical custody could increase stability by reducing each parent’s ability to move after separation. A child alternating between homes may therefore be less likely to experience residential moves, school changes and other forms of spatial instability compared to a child living with one or the other parent. A recent study in France found that mothers with sole physical custody were more likely than those with shared physical custody to remain in the couple’s home, but that when the mother moved, the distance was less for those with shared than for those with sole physical custody (Ferrari et al. 2019). Later residential stability might still, however, favor families with shared physical custody.

The economic and organizational demands of shared physical custody may in themselves produce an element of instability, i.e., children or parents decide it takes too much time and effort to sustain. A considerable share of children who live alternately with each parent eventually live only with their mother (Cloutier and Jacques 1997; Kline et al. 1989; Maccoby and Mnookin 1992; Pearson and Thoennes 1990; Pelletier 2016; Smyth et al. 2008; but see Berger et al. 2008). Important to consider, however, is the fact that the maternal household remains a stable part of the child’s life.

Household instability is also a function of who moves in or out. Parental separation is often the first in a series of family changes experienced by children, often followed by entering a stepfamily and sometimes by the birth of half-siblings (Andersson et al. 2017; Thomson et al. 2014). It is not clear whether shared physical custody is likely to alter the stability of children’s households in comparison to maternal or paternal physical custody. Resident children may reduce opportunities for the separated parent to find a new partner, and/or increase the costs for a new couple to live together (Ivanova et al. 2013). Thus, it is not surprising that mothers with shared physical custody are more likely to re-partner than mothers with sole physical custody, while fathers with shared physical custody are less likely to re-partner than fathers without physical custody (Bakker and Mulder 2013; Juby et al. 2005; Schnor et al. 2017). Chances for children to acquire a step-parent would therefore not necessarily change with shared physical custody, but the children would be more likely to acquire a step-father and less likely to acquire a step-mother, compared to children whose mother has sole physical custody. Children’s coresidence could increase the costs of childbearing in stepfamilies, but evidence for an association between children’s coresidence and stepfamily births is mixed (Vanassche et al. 2015; Vikat et al. 2004).

We might expect shared physical custody to cement the child’s relationship with each parent, and therefore minimize any changes associated with a parent’s re-partnering or births of younger half-siblings. When mothers have sole physical custody, father-child relationships appear to be weakened when the father re-partners or has children in a new partnership (Cooksey and Craig 1998; McGene and King 2012; Seltzer 1991; Swiss and Le Bourdais 2009). Findings are mixed with respect to re-partnering of mothers with sole physical custody (Berger et al. 2012; McGene and King 2012; Seltzer and Bianchi 1988; Seltzer et al. 1989).Footnote 4 Poortman and van Gaalen (2017) reported that father’s re-partnering was associated with a shift from shared to maternal physical custody, but mother’s re-partnering had no parallel effect, suggesting that even when physical custody is shared, the maternal household may be somewhat privileged.

Because coresidence is a critical element in the establishment of family ties, the roles of step-mother and step-father are transformed by shared physical custody. Both step-mothers and step-fathers will be expected to provide material support to the step-children who live with them a substantial part of the time (Ganong et al. 1995; Maclean et al. 2016). Children living alternately with each parent will also be more likely to live with their father’s step-children than if they were living only with their mother. And if their step-father shares physical custody of his children, they share a household at least some of the time with another set of step-siblings. With the birth of half-siblings, the older children moving back and forth will live part of the time with a younger half-sibling, part of the time without; or they may live part of the time with one half-sibling (from the mother) and part of the time with another (from the father). Relationships with and obligations to step-parents, step-siblings and half-siblings have been shown to be more similar to their biological counterparts, the longer the period of coresidence (Arránz Becker et al. 2013; Bressan et al. 2009; Kalmijn 2013; Pollet 2007; van Houdt et al. 2018). Thus, shared physical custody has the potential to strengthen ties between children and all members of their larger and complex family, despite the potential negative effects of household and family instability.

4 Coresidence and Kinship

The effects of coresidence on family relationships also extend to the wider kinship network. Of course, children remain biologically related to both parents’ kin after separation. Because children’s kin relationships are mediated by their parents (Chan and Elder 2000; Whitbeck et al. 1993), however, their contact with extended kin depends on where they live and on the nature of relationships between former in-laws.

Most research finds that parental separation reduces contacts and close relationships between children and their paternal grandparents, while contacts and relationships with maternal grandparents remain the same or are increased (see review in Jappens and van Bavel 2016). The difference arises, of course, from the fact that most children live with their mothers. The shift toward maternal kin is exacerbated by the fact that women are traditional kin-keepers even in nuclear families (Chan and Elder 2000). Maintenance of relationships with paternal kin therefore depend on the mother’s relationships with her former in-laws, especially the mother-in-law (Coleman et al. 1997; Doyle et al. 2010; Goetting 1990).

The reverse occurs when children live full-time with fathers, i.e., they have more contact with their paternal than maternal kin (Hilton and Macari 1997; Lussier et al. 2002; Weston 1992). This suggests that families with shared physical custody would have equal opportunities for maintaining relationships between children and both sets of kin. A few studies have shown that this is indeed the case, and that contact is similar to that of children living in nuclear families (Jappens 2018; Jappens and van Bavel 2016; Westphal et al. 2015).

5 Conclusions

We claimed at the start of this essay that shared physical custody produces a new family form, different of course from nuclear families, but distinct in organization and relationships from separated families where one parent has physical custody and the other does not.Footnote 5 One might argue that the gender egalitarian structure inherent in shared physical custody can be found among coresident parents. Or that parents without physical custody may provide considerable support and relief from childcare responsibilities for the parent with sole physical custody. And that parents and their kin may make extra efforts to maintain contact and relationships with the parent who does not have physical custody.

It is difficult to argue, however, that children’s commuting from one home to another is anything like living in one home. Or that each parent having the full-time responsibility for children while the other has time off from childcare is anything like the egalitarian nuclear family where both parents are simultaneously earning and caring, and trading off only occasionally or by the hour rather than the week. As we argued, these structural features of shared physical custody create distinct contexts for parent-child and sibling relationships and produce differences in shared understandings of obligations between family members. The unique context for relationships and obligations together constitute a new family form.

Shared physical custody highlights the distinctions between family relationships and household membership that become salient when parents separate. When children reside in and feel at home in both parents’ households, their relationships with stepparents and step-siblings are altered. Shared physical custody places more demands on step-mothers and fewer on step-fathers, compared to arrangements where children live with their mothers (and step-fathers) but not with their fathers (and step-mothers). Shared physical custody also provides greater opportunities to develop relationships with the father’s as well as the mother’s step-children (step-siblings). Relationships with both paternal and maternal half-siblings are developed in a shared household. Beyond the two households, children’s ties to paternal as well as maternal kin, and even to step-kin, are likely to be stronger. From the child’s point of view, the boundaries of the two households may be viewed as the boundaries of their family, parallel to the coincidence of household and family boundaries in a nuclear family.

Parents with shared physical custody are to some extent rewriting the gender contract, i.e. “social agreements on what men and women are, what they think and expect, and what they do” (Duncan 1995: 265). Whether they are motivated or not by gender equality in earning and caring, they are de facto in the vanguard of completing the gender revolution (DeRose et al. 2019). Shared physical custody appears to generate the best of both traditionally ‘male’ (access to paid work) and ‘female’ (access to children) worlds.

Some have argued that shared physical custody may be increasing too fast. The political and legal shift toward shared physical custody was initially driven not by mothers seeking more engagement from fathers, but by fathers seeking more rights over their children (Masardo 2009). Shared physical custody may also have outpaced increases in nuclear-family gender equality. When mothers have been primary parents before separation, the assumption that fathers should become equal parents afterwards can be viewed as unrealistic and unfair (Fransson et al. 2016; Harris-Short 2011). As Harris-Short (2010) puts it: “… equality cannot be conjured out of nothing at the point of separation. It must be firmly rooted in the practices of the intact family” (p. 270).

Nevertheless, shared physical custody is now the experience of a rapidly increasing proportion of separated parents and their children. Where it is most common, societal institutions are already in place or relatively easily modifiable to make it work. The ability to afford two homes and to manage children’s commutes between homes is made easier by direct payments to parents; ubiquitous and affordable preschool and after-school care; leave to care for sick children; and housing subsidies for low-income parents. Other policies related to labor markets and conditions of work (employers, shifts, hours, etc.) may also provide opportunities or constraints for shared physical custody (Bakker and Mulder 2013). Where occupations are highly gender-segregated such that female-dominated occupations allow more work-family balance than male-dominated occupations, sharing care responsibilities will be more difficult for many heterosexual couples (Eriksson 2018).

Housing availability may also constrain parents’ possibilities to provide two homes for children. If housing is scarce, it is not simply the double cost of housing, but the possibility of dramatically increasing prices in an area that make it impossible to find another household of similar quality nearby. Shared physical custody is inversely associated with distance between parental homes (Bakker and Mulder 2013; Kitteröd and Lyngstad 2012), and shifts from shared to sole physical custody are more likely to occur when parents live further apart (Poortman and van Gaalen 2017). Housing costs also underlie the positive association between parents’ education or income and shared physical custody (Fransson et al. 2018; Kitteröd and Lyngstad 2012; Pelletier 2016).

Although research on shared physical custody has burgeoned in the past several years, its primary concern has been with the implications of such arrangements for children’s and parents’ wellbeing. Investigations into the structure of daily life, the development and maintenance of parent-child and sibling relationships, implications for step-families and extended kin, have only begun. The theoretical implications of shared physical custody for conceptualizations of households and families and for gender contracts are only beginning to be understood. Empirical research is concentrated in a relatively small number of societal contexts, limiting understandings of how social policies and institutions facilitate or hinder the construction and maintenance of family life when separated parents share physical custody and children move back and forth between two parental homes. This essay provides, we hope, a roadmap for further investigations of the new family form.