As common sense would suggest and as research confirms, children tend to do best in stable households, where they know what to expect and feel (perhaps unconsciously) that their relationships, health, and safety are basically secure. Undergoing repeated transitions can cause stress by threatening this feeling and undermining kids’ and their parents’ sense of control over their lives, which then tends to worsen parenting and to lower children’s academic achievement and mental health.

Unfortunately, instability is an extremely common experience in American kids’ lives today, according to research collected by the Urban Institute. By the time they’re in fourth grade, more than one-third of children will experience a change in their parents’ relationship (whether marriage, separation, divorce, re-marriage, or the beginning or end of a cohabiting relationship). Changes in child care providers and schools are also common: the average child care arrangement lasts only one year, and as many as one in three fourth graders has switched schools at least once in the past two years. Twelve percent of all Americans change residences in a given year, and two in five adults living with kids suffer a major drop in income (of at least 25 percent) during the course of a year. Especially since the recession, tens of millions of families have experienced a period of unemployment or under-employment, with the financial and mental health challenges that accompany them.

Despite their similarities, all these types of transitions are seldom studied in tandem—a fact that inspired the Urban Institute to launch a project exploring the effects of all forms of instability on children’s development and identifying specific areas for future research. The latest publication of that project, which collects the insights of a meeting of scholars, policy-makers, and practitioners, offers a useful primer on important aspects of instability, the ways it affects children, and the implications of these areas for public policy.

Aspects of Instability

Sometimes a transition in a child’s life is positive: for instance, a parent receives a promotion at work that results in higher income and the family’s move to a neighborhood with better schools. In the short term, moving and changing schools may be stressful for the child; however, in the long term, that episode of instability may benefit him or her. Families’ anticipation of and control over transitions can shape their impact; a parent’s long-planned choice to leave the labor market to finish a degree will affect the family differently from an unexpected lay-off, even if the drop in income is the same.

The magnitude, frequency, and spill-over of instability also matter: A minor, one-time, temporary drop in family income would likely have less impact on a child than, say, repeated moves to different cities, or a divorce that led to a significant loss of household income as well as a change of residence and schools. Chronic instability—experiencing transitions so often that instability becomes the norm, as it does for many low-income families—may create toxic stress, which increases children’s risks of all kinds of health and social problems.

Finally, many background factors affect the impact of a given transition. The age, gender, race/ethnicity, temperament, and past experiences of a child; the mental health, parenting skills, employment, and past experiences of a parent; the nature of a family’s social network and local community—all these factors and others contribute to exactly how a transition plays out in the lives of parents and children.

The Ways Instability Affects Kids

As mentioned above, instability creates stress and can threaten children’s and parents’ sense of security and control over their lives. “Specifically,” the Urban Institute meeting participants noted, “stress can directly affect parental mental health and the ability of parents to parent; shape children’s sense of security, trust, and efficacy; affect executive functioning and ability to make proactive future oriented decisions for both children and adults; and…create ‘learned helplessness.'”

Instability also frequently entails a loss of resources, whether of parental time and attention, household income, access to health care, or proximity to supportive relatives and friends, all of which obviously matter for children’s successful development. Furthermore, those are often precisely the resources that could have helped a family to minimize the negative effects of instability, meaning some transitions not only cause problems directly but also leave families less equipped to manage the problems they’re facing. (For instance, a parent’s job loss may cause stress and a drop in income, problems that would be easier to address if they did not also force a family to move to a new city away from their established network of support.)

Implications for Policy

Although many aspects of the safety net, such as unemployment insurance, food stamps, and cash welfare benefits, are designed to mitigate the negative effects of common forms of instability, sometimes public programs can contribute to instability. Certain policies and programs are tied to a family’s residence in a certain area or to a parent’s employment status, which means that a move or a job loss may have the added effect of forcing a change in child care arrangements or forfeiting access to housing assistance. Thus the primary suggestion for policy-makers on instability is to “do no harm,” or to ensure that the eligibility requirements for aid programs do not unnecessarily worsen the impact of negative forms of instability. Despite the possible costs, reforming programs along these lines should make them more effective.

Meeting participants also called for the collection and sharing of data on instability, and for schools, health care providers, social workers, and others to use that data to identify and support families suffering from instability. Such data sharing would help service providers to address all of a family’s intersecting problems, and it could help parents to mitigate the negative impact of instability on their kids.