On days that parents bicker, both mothers and fathers are much more likely to also have tense days with their children, according to a new Cornell University/University of Arizona study.

And although mothers, in general, have conflicts with their children about 40 percent more often than fathers do, fathers are twice as likely as mothers to argue with their kids on days they argue with their wives than on other days.

"Whether mothers work full-time or not, however, seems to be key as to whether fathers experience a lot of so-called tension spillover from the marriage to the children," said Elaine Wethington, a medical sociologist and Cornell associate professor of human development and family studies. "In families where mothers were employed full-time, we found that fathers were twice as likely to experience tension spillover compared with families in which mothers did not work full-time."

Wethington and David Almeida, a developmental family psychologist and professor of family studies at the University of Arizona, analyzed the tension and stress entries in diaries kept for six weeks by 113 white married fathers and mothers living near Detroit. Their goal was to determine whether parents are more likely to have tense interactions with their children on days they experience conflict with their spouses.

Whereas previous studies on tension spillover have compared families, this study is the first to examine tension spillover within families for any length of time. The findings were presented to the Society for Research on Adolescence in Boston in March.

Specifically, the researchers found that during the 42-day period:

• Couples, on average, reported marital tension more than 5 percent of the days studied.
• Mothers reported tension with their children on about 10 percent of the days studied; fathers reported tensions on 6 percent of the days.
• When parents argued, mothers were three times more likely and fathers six times more likely to have conflict with children.
• Other daily stressors, such as work overload or home demands, doubled fathers' tension spillover to their children, but did not affect mothers' tension spillover. This effect of having a bad day seems to be concentrated among fathers in families where mothers are employed full-time, Almeida said.
• Each additional child in the family increased the likelihood of mother-child tension by 36 percent, while having adolescents decreased the likelihood of mother-child tension by more than 50 percent.

In previous research, Wethington, in collaboration with University of Michigan researchers Niall Bolger, Anita DeLongis and Ronald C. Kessler, found that "stress spillover" occurs between home and work quite readily, especially among men. Husbands were three times more likely than wives to have conflict at work after having arguments at home. Husbands and wives, however, were equally likely to have stress at home after a bad day at work.

More recently, Almeida and Wethington found that the more time fathers spend caring for their children, the more arguments they had with them, especially when fathers were in a bad mood.

These findings might explain why Wethington and Almeida found such gender differences in their marital stress spillover study.

"Since fathers don't tend to spend as much time with their children, they are less likely to argue with them," Almeida said. "When they do argue with children, the cause seems to be more likely due to a spillover effect. Mothers also appear to be better at compartmentalizing their stressors, not allowing stress from one arena to spill over into another arena."

The researchers suspect that the reason why men of employed wives are much more likely to fight with kids on days they've argued with their wives, compared with other men, could be because these fathers spend more time caring for the children. More home responsibilities puts more demands on fathers and more opportunities for conflicts with children. Also, when women work full-time, they may have depleted energy to protect the family from spillover stress, Almeida said.

"We've found overwhelming support that tension from marriage spills over into the parents' relationships with their children," the researchers said. "However, we must remember that positive interaction and harmonious relations are also contagious. Sharing accomplishments, laughter and joy with a spouse are certainly likely to engender positive interactions with children and vice versa."

Currently, the researchers are interviewing a representative sample of 1,500 people nightly for eight days to explore more deeply conflicts of the day and their spillover effects.