READ MORE: The Fatherly Guide to Raising Brothers and Sisters “My way of thinking is that our society just doesn’t have standards and norms that say siblings should not be hitting each other,” says Feinberg. “At least not in the way we have the same kind of standards and norms around couples.” Though other social standards for physical aggression among family members have changed — it’s now widely accepted you shouldn’t spank your kid for punishment–the idea that it’s normal for brothers and sisters to hit each other has not really shifted. In fact, there’s a persist strain of parental anti-wisdom suggesting sibling conflict can prepare kids for adult relationships outside the home. “That’s false,” says Feinberg. “The more conflict there is in a sibling relationship, the more those kids are likely to go on negative trajectories. They’re not learning how to resolve disagreements. They’re not learning how to get along with people. Unregulated sibling conflict is just not a good thing.” Many parents suspect that conflict can be addressed by scolding an older child. This idea emerges from the assumption that older children govern their relationships with their younger siblings. That is not necessarily true. Kids, especially young kids, can’t really steer a relationship regardless of the power dynamic. And the power dynamic is hardly a given. Feinberg notes that many younger siblings give as good as they get. That sentiment is echoed by psychologist Dr. Susan Newman. “It is not always older siblings who are the bullies,” she explains. “This is especially true when the younger siblings catch up in both size and/or verbal ability.” Newman points to her own life as an example, saying that she was a younger sister who “tormented” her big brother, an antipathy never acknowledged by her parents. “They, like many parents, didn’t want to believe that a child they treasured could be such an aggressor,” she says. And that points to a parent’s role in kids being aggressive with one another: Determining the truth. There isn’t just conflict. There are aggressors. There isn’t just violence. There are provocations. Parents need to know what’s what and there’s really only one way to do that: Keep a weather eye. “To keep bullying at bay, parents need to pay attention,” Newman says. “When a child complains, parents should listen and take action if needed. Too many parents dismiss children’s complaints as sibling rivalry or a stage that the children will out grow.” “Sibling relationships are so tricky,” adds Feinberg. “Because siblings spend more time with each other than they spend with anyone else in the world on average.” The temptation for parents is to see all those interactions in aggregate, but only by addressing the individual instances of button-pressing can a parent bring both parties to the table and forming a lasting peace (yes, the verbiage has the distinct twang of Middle Eastern conflict). “If parents can help their kids problem solve their disagreements by acting as a mediator rather than an authoritarian, that seems to help kids get along better,” Feinberg says. “The family needs to have a rule–that might be ‘No physical aggression’—then be firm about that.” Treaties exist for a reason. Finally, Feinberg notes that it helps when parents accentuate the positives of the sibling relationship. He suggests this works best when a parent is working with both kids to find activities that they can both enjoy–then remain involved in the activity. And, if all else fails, a parent should never be ashamed to head towards family therapist for an assist, particularly if one child exhibits more aggression than normal. In the end, maybe that was what led to the first murder: too few therapists.