As countless unmade beds and unfinished homework assignments attest, kids need rules. Yet how parents make demands can powerfully influence a child's social skills, psychologists at the University of Virginia recently found after the conclusion of a study investigating the notorious transition from adolescence to adulthood.

Initially 184 13-year-olds filled out multiple surveys, including one to assess how often their parents employed psychologically controlling tactics, such as inducing guilt or threatening to withdraw affection. The kids rated, for example, how typical it would be for Dad to suggest that “if I really cared for him, I would not do things that caused him to worry” or for Mom to become “less friendly [when] I did not see things her way.”

The researchers followed up with the subjects at ages 18 and 21, asking the young adults to bring along a close friend and, later, a romantic partner if they had one. These pairs were asked to answer hypothetical questions that were purposefully written to provoke a difference of opinion. “We wanted to see whether they could navigate a disagreement in a healthy way,” says study leader Barbara Oudekerk, now at the U.S. Department of Justice's bureau of statistics.

In the October issue of Child Development, Oudekerk and her colleagues report that the 13-year-olds who had highly controlling parents floundered in friendly disagreements at age 18. They had difficulty asserting their opinions in a confident, reasoned manner in comparison to the kids without controlling parents. And when they did speak up, they often failed to express themselves in warm and productive ways.

The researchers suspect that manipulative parents undermine their child's ability to learn how to argue his or her own viewpoint in other relationships. Although parents do need to set boundaries, domineering tactics imply that any disagreement will damage the bond itself. Separate findings suggest that parents who explain the reasons behind their rules and turn disagreements into conversations leave youngsters better prepared for future disputes.

The consequences of tense or domineering relationships appear to compound with time. This study also found that social difficulties at 18 predicted even poorer communication abilities at age 21. Psychologist Shmuel Shulman of Bar-Ilan University in Israel, who did not participate in the work, thinks these conclusions convincingly reveal how relationship patterns “carry forward” into new friendships.