HBO's limited-run series "Big Little Lies" has won acclaim for their handling and realistic portrayal of an abusive relationship.

The show also touched on how an abusive relationship can affect the children of that relationship — even if the parents aren't aware it is.

Spoilers on the season finale of "Big Little Lies" are ahead!

If you are not caught up with the 7 episode series, now is the time to stop reading if you want to avoid spoilers.

In the finale, it's revealed that Celeste's abusive husband, Perry, is the same man who raped Jane years ago, resulting in Jane's son, Ziggy. Earlier in the show, parents accused Ziggy of hurting one of his classmates, Amabella. Ziggy never showed violent behavior in earlier episodes.

In another twist, it turns out that one of Celeste and Perry's twin sons, Max, was actually the one abusing Amabella.

The show is making a point here: that Ziggy and Max, despite having the same violent father, turned out differently.

It turns into a classic nature vs. nurture argument: Are people a certain way because that's how they were born, or because they learned to act that way, as Max did when it's suggested (via quick cuts in editing) that he saw and heard his father continuously abuse his mother? (To paraphrase Celeste, when Perry insists Max hadn't picked up on his violent behavior: "How couldn't he have?")

Some say it's genetic.

CBS News reported in 2002 that "a single gene may explain why some boys—but not all—abused in childhood grow up to become violent or aggressive" citing research in the Science journal.

Studying over 1,000 children of both genders, the researchers found "85 percent of the boys who had a weakened version of the gene and who were abused turned to criminal or antisocial behavior." They focused on "a gene that controls production of an enzyme called monoamine oxidase A."

However, the researchers also noted how these children were raised. Lead researcher Terri Moffitt told CBS News, "By age 11, 36 percent of the subjects had been maltreated (8 percent severely), as defined by frequent changes in primary caregiver, rejection by the mother and physical or sexual abuse" Their conclusion? "If the abused boys had one version of the MAOA gene that caused their brains to produce too little of the enzyme, they were nine times more likely to become antisocial."

Some say it's learned.

Lt. Col. David L. Thomas II, Field Artillery Officer, wrote for Military.com in 2005 that "violence is actually a learned behavior. We learn violence from a variety of sources." He cited the American Psychological Association who reported "After reviewing hundreds of research findings, three major national studies have concluded that heavy exposure to violence is one of the most significant causes of violence in society."

"Aggressive children become aggressive adults," he states. "Children exposed to violence will more than likely become violent adults. An estimated 3.3 million children are exposed to violence by family members against their mothers or female caretakers."

And Science Daily reported back in 2000, before any of these stories, on a study done at Wake Forest University Baptist Medical Center which concluded "violence is a learned behavior." The study asked over 700 children in middle school who lived in or around public housing "how many times they had been exposed to or had been a victim of violence in their communities."

The sad answer? "Only 1.4 percent of the students had not witnessed or been the victim of any violence and 54.1 percent of all students reported witnessing or being the victim of between one and 15 acts of violence."

Robert H. DuRant, the study's author (and vice chair of pediatrics at Wake Forest University School of Medicine) said of his findings, "This study has tremendous implications. Even if children and adolescents are exposed to other risk factors that have traditionally been linked to youth violence and weapon carrying, adolescents are not likely to engage in violence if social learning from exposure to violence does not occur."

Now that's big.