Sept. 16, 2009 -- Growing up, Nick Schiavone feared his father. Now a single father of two himself, he tries hard to be affectionate and demonstrative with his own children, he said. But when Nicholas, his 5-year-old son, acts up, Schiavone's temper can get the best of him.
"I will slap the crap out of you!" Schiavone yelled, with cameras rolling, after the boy threw a rubber toy at his face.
It's hard enough for any parent to know what to do when a child acts out. For caregivers who themselves were disciplined with harsh physical punishment as a child, it's even harder. Studies show that one in three people who were abused as children will grow up to become an abuser.
For more than a month last year, ABC News followed three parents in Florida who are trying to overcome the odds. Cameras rolled as the parents struggled to deal with their kids monster tantrums and meltdowns that could test anyone's patience. The families volunteered for a mentoring program for at-risk parents called Parent Aide, run by the Toledo, Ohio-based National Exchange Club Foundation.
Schiavone said that nowadays he has a very good relationship with his dad -- but when he was young, things were different.
"When I was younger he was kind of abusive," Schiavone told ABC News' Chris Cuomo. "Spanking, punching, throwing me across the room. I don't want to do that with my children, because I know the effect that it put on me as a human being. I don't want that to happen to my children."
Can these parents stop the cycle and not perpetuate the violence they themselves experienced as children? They'll get help, but will they be able to help themselves?
Experts are shedding light on parenting techniques that can help break the cycle and can provide a blueprint for virtually anyone looking to become a better parent. Science has shown that stress hormone levels in children, aggression and even obesity can be altered when parents learn how to break the cycle of damaging behavior.
"Most parents who were abused as children say, 'I'll never treat my children the way I was treated,'" said Karen Askew, director of the National Exchange Club Foundation. "But people tend to parent the way they were parented themselves."
Cora and Her Grandchildren
Cora Colquhoune, 63, has had custody of her grandchildren -- Tim, 10, Alex, 9, and Talia, 6 -- since they were infants. Their mother has been in and out of jail several times, and the children's father is in and out of their lives. It's all that Colquhoune, a retired cook, can do to keep up with three young children.
When she's at wit's end, Colquhoune says she falls back on how she was raised: She threatens physical punishment.
"I just want to kill him," Colquhoune said after a run-in with one of her grandsons. "I just want to pick up one of them pots right there and smash his damn head. ... If you discipline the children the way I would discipline, they'd a put me in jail, in prison."
Colquhoune said she's struggling to raise her grandkids without force. But the older they get, she said, the harder it is for her to control them.
In one videotaped scene, Tim swats his little sister, Talia.
"Stop!" Colquhoune yells, backhanding the boy in the stomach.
Then Tim hits his grandma back -- and runs.
Colquhoune gives chase, but has a hard time catching the 10-year-old. She throws a shoe at him and misses.
"You're not going to hit her no damn more," she tells him. "You get out of here."
In another scene, Colquhoune advances on Talia with a wooden spoon. But she wouldn't use it, she said.
"I haven't hit one of them yet. I've never hit one of them with this. But this is my threat right here," Colquhoune said. "I also got a fly swatter right there."
Dr. Alan Kazdin heads up the Yale University Parenting Center and Child Conduct Clinic. He is the author of "The Kazdin Method for Parenting the Defiant Child" and other books on parenting.
Kazdin says kids learn by example -- so parents have to be careful about what behavior they model.
"If you want this child to comply and show respect, you don't start screaming and shouting and making threats," Kazdin said. "That will only make it worse."
He said that even if Colquhoune had used the fly swatter, it would not change the child's behavior for long.
"We know that the behavior will be suppressed at that instant," Kazdin said, "and it won't change over time. If she escalates to worse and she makes stronger threats and more hits, the child will adapt immediately. So that doesn't make her threats more effective. It makes all of them ineffective. It doesn't work."
Fortunately, Colquhoune reached out for help in navigating this rocky road. When she volunteered to take part in the Parent Aide program, Jean Hammond became her parenting mentor. Hammond has been at the job for 14 years, and it doesn't take her long to recognize a familiar pattern.
"[Cora] finds herself not able to discipline them," Hammond told ABC. " I think she is just a soft-hearted person. And she's let them get away with that, over the years. So when she says something to them, they don't do it."
And what about the parent who doesn't use physical force or threats, but still can't get her child to behave?
Dawn, 36, said she remembers being hit so much as a child it made her completely shut down. "Even when I did something nice, I got spanked," she told ABC News. As a result, she said, she became a rebellious teen.
"I didn't listen to anyone," Dawn said. "I had anger. I was angry at the world. Wanted to do what I wanted."
And now, Dawn said, she has begun to notice that same rebelliousness in her 4-year-old, Autumn.
In scenes taped at her home, Dawn comes across as both loving and, at times, extremely critical.
"Autumn, stop playing with your food, please," Dawn says in one scene. "Uh-uh, don't wipe that on yourself, use a napkin. Autumn, wipe that on the napkin please. Don't use your clothes -- napkin! I'm taking it away."
And even when Autumn tries to correct her behavior, it's as if the little girl can do nothing right.
"Sit down the right way," says Dawn.
"Oops -- sorry," says Autumn.
"I'm sick of this behavior, you're gonna go to bed, you do not sit there and pour things on the floor!" scolds Dawn. "Go to timeout!!"And mom drags daughter out of the room, picking her up to carry her. Autumn screams.
Jacqueline Ligon is Dawn's parenting mentor.
"When we first started working together, she was very meek and not very assertive," said Ligon. "We've really worked hard at taking charge of, you know, not always being a victim."
So Ligon suggested some basic techniques to use when disciplining autumn: timeouts, restricting privileges and taking toys away.
But at first, Dawn was so desperate to control her daughter's tantrums that she ended up throwing every punishment she could think of at Autumn all at once.
"Go to timeout, I'm not playing, go to timeout!" says Dawn in one scene. "OK Autumn, no TV tonight or anything. You're about to lose one of your stories. That's it, no Popsicle tonight!"
Reinforcing the Positive
Even appropriate disciplinary measures become ineffective if they are too liberally applied, Kazdin explained.
"You don't just pull out your holster and shoot a timeout at this and then at that," he said. "If you do two timeouts in a day or three timeouts in a day, your program is wrong."
In fact, Kazdin says that punishment -- the one thing most parents reach for in their arsenal -- is not the magic bullet after all.
"Think of that horrible situation, there's someone drowning," said Kazdin. "You could never teach a person how to swim at that point. You have to just contain the situation and get 'em to shore."
The secret weapon that research shows beats yelling, timeouts, correction and any kind of punishment you could possibly throw at your child?
Experts say nothing else gets children to obey like telling them what they are doing right.
"Go in that room and say, you know, 'You guys have been so quiet, this is amazing, you're getting along, that's fantastic. Let's do extra TV tonight,'" said Kazdin. "If you're not doing that, don't even fool with time out, it's a waste of time.
"If you're not reinforcing the positive, you're going to frustrate yourself endlessly."
Watch "Primetime" tonight at 10 p.m. ET to find out how Schiavone, Colquhoune and Dawn changed their approaches to parenting -- and how it worked out. Click HERE for Dr. Alan Kazdin's 10 Tips for Parenting a Defiant Child.