When Roger Lockridge has to ponder what he should do as father to his 3-year-old son Roger Wayne, he ask himself what his own father would have done.

Then he usually does something else.

Lockridge is a childhood domestic violence (CDV) survivor. Now 34, the Dawson, West Virginia, man often saw his mom and dad fight. The last time was when he was 10 and his mom said she was leaving and taking the kids. The man held his wife, his kids and their grandmother at gunpoint for nearly 90 minutes, until he felt they were so intimidated that he could go outside and disable the car. He was drunk and about to pass out, Lockridge says. Lockridge's mom called police.

For four months, mom and kids lived in a domestic violence shelter, where they got therapy and practical assistance as his parents divorced.

Although his mother was physically abused, not him, Lockridge lived in the shadow of domestic violence — just like 15 million American children today and an estimated 40 million adults who lived with it as kids, according to Brian F. Martin, CEO and founder of the Childhood Domestic Violence Association.

"It's surprising that it's not discussed more," said Martin. "Most people don't know what childhood domestic violence is. It's when you grow up in a home where there's violence between parents or toward a parent, perhaps by a significant other."

Some experts call it "child witness to violence," a name Martin said fails to capture the damage it inflicts.

He knows. Growing up, he saw his mother's boyfriend beat her. It took him years to get over the idea that he, a little boy then, should have stopped it.

Naming and assessing

Experts have struggled with what to call it when children witness violence at home, said Martin. It's not the same as child abuse, physical abuse, domestic violence, sexual abuse or emotional abuse, though some of the children experience those, too. Martin numbers CDV among "about 10 adversities researchers say we can experience in childhood homes. … If you have one, you usually have more than one. … This is the one they don't talk about or fully understand."

CDV encodes what he calls a "series of negative beliefs" in the child's self-concept.

In a 2012 presentation, Betsy Groves, founder of the Child Witness to Violence Project at Boston Medical Center, said witnessing domestic violence teaches children no place is safe, no one can protect them and adults are vulnerable. Those children say their fear leads to aggression.

Children are not equally affected by seeing domestic violence, but it's a "particularly toxic form of trauma" for them; witnessing it may psychologically traumatize a child as much as being the direct victim, she said.

A UNICEF report found "children who live with and are aware of violence in the home face many challenges and risks that can last throughout their lives," including greater risk of being abused, increasing harm to the child's physical, emotional and social development, and a good chance it will kick off generational violence.

Martin said a researcher told him "who we believe we are is decided before we ever have a chance to choose. Then the brain finds evidence of what it believes is true." Martin felt like a "very weak coward" for not stopping the assaults on his mother. As he grew up, he said his mind found evidence to support it.

Feelings of guilt and shame kill willpower, he noted.

Among ways Martin said CDV strikes:

• Health. "The leading 10 causes of death are linked to these homes. It ages your DNA," he said. He notes those people are six times more likely to kill themselves, 50 times more prone to addiction and 74 times more apt to be violent. While most won't be violent, their lives don't go the way they want, either.

• Emotional. "It's very hard to find happiness if you believe terrible things about yourself," Martin said.

• Relationships. "The best predictor of whether you will be in a violent relationship is whether you grew up in one. No one addresses that. It's like trying to reduce the incidence of lung cancer without addressing smoking," he said.

"Silence is a problem, along with judgment from those who didn't experience it, who say to just get over it. … The first step is knowing what it's called, then seeking to understand it. Then you need to share it with someone who you know cares about you. It's amazing what those three steps can do."

Lingering legacy

"There are times still when I lack self-confidence, though I am an accomplished writer and recently bought my own home," said Lockridge. "I think that stems from my experience as a kid."

CDV never completely stopped affecting Lockridge, who has spoken publicly about it many times and wrote his story for Martin's book "Invincible: The 10 Lies You Learn Growing Up with Domestic Violence and the Truths to Set You Free." "I did not want my wife and children, if I was going to be blessed to have any, to experience this," he said. "It shapes how I conduct myself as a husband and as a father. Everything I have seen my parents go through, I try to do the exact opposite.

"Both my parents were alcoholics; I've never tasted alcohol. My dad bounced between jobs and when he was unemployed, mom had to carry the load. My wife doesn't have to work. If she wants to get a job, she can, but she doesn't have to," he said. Of his little boy, he adds, "I hope when he's an adult, he will tell others how great a dad he had."

Years later, after his dad finished rehab and stopped drinking, he re-established bonds with his children, a year before he died. Lockridge said not all of his siblings had the same experience or memories of a violent family life that he did. "My younger brother has no negative memories of my dad and my baby sister has no memories of him at all," he noted, because of their age when the family split. Older half-siblings were grown before his parents got together.

The UNICEF report said all children need a safe home environment and to know that "there are adults who will listen to them, believe them and shelter them." They also need routines, support services and to learn domestic violence is wrong. An important aspect of that is learning nonviolent conflict resolution techniques.