In the 1980s and 1990s, there was a sense that fathers were irrelevant in child-rearing, said Hiram Fitzgerald, a distinguished MSU psychology professor.

"People thought they just sort of made the money and paid the bills, and didn't have much else to do," he said.

Eleven years, 3,000 families and 800 fathers later, Fitzgerald has seen the impact the fathers have on their children.

Fitzgerald is part of a national evaluation of Early Head Start families. His research on low-income families involved a father's influence on children.

One of the biggest surprises he found was fathers were present in family life much more than he expected.

"Much of the media suggests dads are not around in low-income families," he said.

Out of 3,000 families, 64 percent had biological fathers, and others had social fathers - a male figure that had been living with the family for at least 9 months.

After studying the families through videotapes, observations, interviews and structured and unstructured tasks, he found fathers have two main ways of parenting and interacting with their children - they energize them but are quick to discipline.

Fathers engage in "rough and tumble play," Fitzgerald said.

"Fathers tend to let their children take more risks while getting kids excited," he said.

But the fun is put on hold when children get too out of control.

"They bring them back into control usually with some quick, stern discipline," Fitzgerald said.

The parenting techniques were best illustrated while watching one of the fathers interact with his three young children, he said.

The children, a 5-year-old and two toddlers, were rolling around on the floor, laughing and playing, Fitzgerald said.

The 5-year-old turned to one of his younger siblings and kicked him.

The giggling immediately stopped as the father simply said to the 5-year-old, "Hold it. We don't do that."

The child was exposed to a rule with no explanation, Fitzgerald said, and it was effective.

"It was a total shutdown of all that enthusiasm and joy," Fitzgerald said. "The immediate discipline and immediate rule ended the behavior."

Families without father figures tended to have kids who had behavioral problems, Fitzgerald said, and there was a difference between the roles biological fathers and social fathers played.

Over time, a biological father spent less time with his children while a social father's time commitment remained the same, Fitzgerald said. But he said there's a perfectly natural explanation.

By the time a child reaches preschool age, a biological father knows him or her pretty well. The time the father has to spend disciplining them is minimal.

"If a father is upset at his 5-year-old, he gives a stern look, and that's all he has to do," Fitzgerald said. "They develop ways of communicating that don't require long amounts of time."

A social father typically doesn't have that relationship with a child right away, and may spend more time with his children to develop those cues.

One thing stood out in the study, he said. Fathers, regardless of economic status, have a critical role in teaching children about behavioral norms.

"Fathers really do matter," he said.

Colleen Maxwell can be reached at maxwel79@msu.edu.