This holiday season, many Americans may need a flow chart to figure how they’re all related. What do you call, for example, your stepmother’s son’s live-in girlfriend’s 11-year-old son?
As family structures become more complicated, a new body of new research is attempting to quantify the trend. The proliferation of stepchildren, half-siblings, and other extended relationships has important implications for how American families function.
Almost a third of U.S. households headed by adults under age 55 have at least one stepparent, according to a recent analysis of survey data by University of Massachusetts Boston Professor Emily Wiemers and others. Similarly, the study found that, looking at couples over age 55 who have adult children, 33 percent have a stepchild.
These step-relationships can stretch both the size and definition of family—researchers included both married and unmarried co-habiting couples in the analysis. For Americans with grown children, counting stepchildren boosts the total number of adult kids by 66 percent, the study found.
The rise in divorce and remarriage is driving this growth in family size. Over the past two decades, the divorce rate has doubled for older Americans. Almost 30 percent of people over 50 had been married more than once, according to a recent study by scholars at Bowling Green State University. About 40 percent of older Americans with children are in stepfamilies, according to survey data.
“People in stepfamilies are often unsure of what their obligations are to their stepkin,” said Bowling Green sociology professor Karen Benjamin Guzzo. “It’s not uncommon for individuals to feel like they have to choose how to spread resources across their biological and step-relatives.”
These questions come up when planning vacations, paying for college, and especially as parents and stepparents age. Couples can fight about how much money or time they owe to children from their previous vs. current relationships.
As complex families get older, and baby boomer stepparents move from middle age into their elderly years, even more questions are raised. For example, when your elderly stepparent needs a ride to the doctor’s office, should you feel the same obligation as you would to a biological parent?
Stepkids can end up with more elderly parents to take care of, and aging parents may have more children to lean on for help. In practice, though, stepfamilies can feel less connected to each other. The Weimers study analyzed survey data to compare how often stepfamilies and more traditional families donate time to each other. Couples with adult stepchildren are 11 percentage points less likely to give time to their children, and 13 points less likely to receive time from kids.
“The increased availability of kin does not fully compensate for the weaker bonds among family members in step families,” the paper concludes.
Of course, many stepfamilies are quite close, and many traditional families never get along. But stepfamilies often need to work harder to bring their sprawling families together.